PC5271 wiki - User contributions [en]

Non-contact Alcohol Concentration Measurement Device At NIR Spectrum

2025-04-01T03:44:25Z

Chengrui: /* 2. Measure Absorbance */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
[[File:ALCOHOL2.jpeg|center|thumb|Ethanol Sample Preparation]]
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
[[File:ALCOHOL.jpg|center|thumb|Ethanol Sample]]
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device At NIR Spectrum

2025-04-01T03:44:01Z

Chengrui: /* 2. Measure Absorbance */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
[[File:ALCOHOL2.jpeg|center|thumb|Ethanol Sample]]
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
[[File:ALCOHOL.jpg|center|thumb|Ethanol Sample]]
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

File:ALCOHOL2.jpeg

2025-04-01T03:43:30Z

Chengrui:

Non-contact Alcohol Concentration Measurement Device At NIR Spectrum

2025-04-01T03:40:01Z

Chengrui: /* 2. Measure Absorbance */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
[[File:ALCOHOL.jpg|center|thumb|Ethanol Sample]]
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device At NIR Spectrum

2025-04-01T03:39:38Z

Chengrui: /* 2. Measure Absorbance */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.
[[File:ALCOHOL.jpg|center|thumb|Ethanol Sample]]

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device At NIR Spectrum

2025-04-01T03:38:32Z

Chengrui: /* 2. Measure Absorbance */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.
[[File:ALCOHOL.jpg|center|thumb|Schematic Diagram of the Experiment]]

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device At NIR Spectrum

2025-04-01T03:36:44Z

Chengrui: Created page with "== Team Member == Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi == Background == Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and la..."

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.
[[File: ALCOHOL.jpeg|center|thumb|Schematic Diagram of the Experiment]]

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Main Page

2025-04-01T03:36:28Z

Chengrui: /* Non-contact Alcohol Concentration Measurement Device At Near-Infrared (NIR)Spectrum */

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[[Non-contact Alcohol Concentration Measurement Device At NIR Spectrum]]===
Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi
This project aims to build a sensor to measure the concentration of alcohol by optical method
(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T03:35:59Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[[Non-contact Alcohol Concentration Measurement Device At Near-Infrared (NIR)Spectrum]]===
Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi
This project aims to build a sensor to measure the concentration of alcohol by optical method
(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:32:33Z

Chengrui: /* 2. Measure Absorbance */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.
[[File: ALCOHOL.jpeg|center|thumb|Schematic Diagram of the Experiment]]

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:32:08Z

Chengrui:

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.
[[File:ALCOHOL.jpeg|center|thumb|Schematic Diagram of the Experiment]]

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:28:19Z

Chengrui:

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:25:43Z

Chengrui: /* 1. Setup the Apparatus */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).
[[File:Alcohol.jpg|thumb|250px|right|Infrared-Based Alcohol Detection]]

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:24:22Z

Chengrui: /* 1. Setup the Apparatus */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).
[[File:ALCOHOL.JPG|center|thumb|Schematic Diagram of the Experiment]]

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:24:09Z

Chengrui:

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).
[[File:Transmittance-ALCOHOL.JPG|center|thumb|Schematic Diagram of the Experiment]]
=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

File:ALCOHOL.jpg

2025-04-01T03:22:14Z

Chengrui:

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:30Z

Chengrui: /* Data Analysis */

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:25Z

Chengrui: /* References */

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:21Z

Chengrui: /* Methodology */

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:18Z

Chengrui: /* 2. Measure Absorbance */

== Methodology ==
=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:13Z

Chengrui: /* 1. Setup the Apparatus */

== Methodology ==
=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:09Z

Chengrui: /* Equipment Required */

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:12:05Z

Chengrui: /* Advantages of Infrared-Based Alcohol Detection */

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:11:59Z

Chengrui: /* Objective */

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:11:47Z

Chengrui: /* Background */

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:11:20Z

Chengrui: /* Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law */

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:10:58Z

Chengrui: /* Methodology */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Preparation of alcohol solutions at concentrations of 25%, 50%, and 75%.
* For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer.

=== 3. Analyze the Results ===
* Use Origin software for spectral normalization and baseline correction, and process the alcohol spectra at three different concentrations.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:03:46Z

Chengrui: /* Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law */

== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:02:14Z

Chengrui: Created page with "= Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law = == Team Member == Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi == Background == Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement..."

= Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Talk:Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law

2025-04-01T03:01:31Z

Main Page

2025-04-01T03:00:45Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[[Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law]]===
Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi
This project aims to build a sensor to measure the concentration of alcohol by optical method
(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T02:59:29Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

===[Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law]===
Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi
This project aims to build a sensor to measure the concentration of alcohol by optical method
(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T02:58:25Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law]===
Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi
This project aims to build a sensor to measure the concentration of alcohol by optical method

(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T02:57:53Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T02:57:22Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law]===

Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi
This project aims to build a sensor to measure the concentration of alcohol by optical method

(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T02:57:06Z

Chengrui:

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

This project aims to build a sensor to measure the concentration of alcohol by optical method

(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Main Page

2025-04-01T02:55:59Z

Chengrui: /* Alcohol Concentration Measurement */

'''Welcome to the wiki page for the course PC5271: Physics of Sensors!'''

This is the repository where projects are documented. Creation of new accounts have now been blocked,and editing/creating pages is enabled. If you need an account, please contact Christian.

==Projects==
===[[Project 1 (Example)]]===
Keep a very brief description of a project or even a suggestion here, and perhaps the names of the team members, or who to contact if there is interest to join. Once the project has stabilized, keep stuff in the project page linked by the headline.

===[[Laser Gyroscope]]===
Team members: Darren Koh, Chiew Wen Xin

Build a laser interferometer to detect rotation.

===[[Laser Distance Measurer]]===
Team members: Arya Chowdhury, Liu Sijin, Jonathan Wong

This project aims to build a laser interferometer to measure distances.

(CK: We should have fast laser diodes and fast photodiodes, mounted in optics bench kits)

===[Non-contact Alcohol Concentration Measurement Device Based on Beer-Lambert Law]===

Team members: Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi

This project aims to build a sensor to measure the concentration of alcohol by optical method

(CK: you can check Optics Letters 47, 5076-5079 (2022) https://doi.org/10.1364/OL.472890 for some info)

===[[Ultrasonic Acoustic Remote Sensing]]===
Team member(s): Chua Rui Ming

How well can we use sound waves to survey the environment?

(CK: we have some ultrasonic transducers around 40kHz, see datasheets below)

===[[Blood Oxygen Sensor]]===
Team members: He Lingzi, Zhao Lubo, Zhang Ruoxi, Xu Yintong

This project aims to build a sensor to detect the oxygen concentration in the blood.

(CK: We have LEDs at 940nm and 660nm peak wavelenth emission, plus some Si photodiodes)

===[[Terahertz Electromagnetic Wave Detection]]===
Team members: Shizhuo Luo, Bohan Zhang

This project aims to detect Terahertz waves, especially terahertz pulses (This is because they are intense and controllable). We may try different ways like electro-optical sampling and VO2 detectors.

===[[Optical measurement of atmospheric carbon dioxide]]===
Team member(s): Ta Na, Cao Yuan, Qi Kaiyi, Gao Yihan, Chen Yiming

This project aims to make use of the optical properties of carbon dioxide gas to create a portable and accurate measurement device of carbon dioxide.

===[[Photodetector with wavelength @ 780nm and 1560nm]]===
Team members: Sunke Lan

To design photodetector as power monitor with power within 10mW.

(CK: Standard problem, we have already the respective photodiodes)

===[[Single photon double-slit interference]]===

Team members: Cai Shijie, Nie Huanxin, Yang Runzhi

1.Build a single photon detector using LED. The possible LED is gallium compounds based, emitting wavelength around 800nm(red light).

2. Other possible detector: photomultiplier or avalanche photon detector(do we have that?).

3.Do single double-slit interference experiment.

Other devices needed: use LED as single photon source (wavelength shorter than the emitting wavelength 800nm)

prove the detection is single photon: need optical fibre, counting module

===[[STM32-Based IMU Attitude Estimation]]===

Team members: Li Ding, Fan Xuting

This project utilizes an STM32 microcontroller and an MPU6050 IMU sensor to measure angular velocity and acceleration, enabling real-time attitude angle computation for motion tracking.

===Fluxgate magnetometer===
Team members: Ni Xueqi

This project uses the fluxgate magnetometer to quantify the magnitude of an external magnetic field generated through coils with varying currents and permanent magnets with varying distances.

===[[CO2 Concentration Detector]]===
Team members: Xie Zihan，Zhao Yun，Zhang Wenbo

Infrared absorption-based CO₂ gas sensors are developed based on the principle that different substances exhibit different absorption spectra. Because the chemical structures of different gas molecules vary, their degrees of absorption of infrared radiation at various wavelengths also differ. Consequently, when infrared radiation of different wavelengths is directed at the sample in turn, certain wavelengths are selectively absorbed and thus weakened by the sample, generating an infrared absorption spectrum.

Once the infrared absorption spectrum of a particular substance is known, its infrared absorption peaks can be identified. For the same substance, when the concentration changes, the absorption intensity at a given absorption peak also changes, and this intensity is directly proportional to the concentration. Therefore, by detecting how the gas alters the wavelength and intensity of the light, one can determine the gas concentration.

===[[Light Sensing System Based on the Photoelectric Effect]]===
Team members: Xu Ruizhe, Wei Heyi, Li Zerui, Ma Shunyu

This project utilizes the principle of the photoelectric effect to design a smart light sensing system. The system can detect ambient light intensity and process the data using Arduino or Raspberry Pi. When the light intensity changes beyond a predefined threshold, the system can trigger responses such as lighting up an LED, activating a buzzer, or automatically adjusting curtains.

===[[Temperature and humidity sensors]]===
Team members: Chen Andi, Chen Miaoge, Chen Yingnan, Fang Ye

This project aims to develop a simple temperature and humidity monitoring system using the DHT11 sensor and an Arduino microcontroller, with real-time data displayed on an electronic screen. The system is powered by a 9V battery, making it portable and suitable for various environmental monitoring applications. By integrating the DHT11 sensor with the Arduino board and displaying the measured data on a screen, this project demonstrates a practical approach to building low-cost, efficient environmental monitoring devices. The project serves as a fundamental prototype for further development in smart home systems, weather stations, and IoT applications.

===[[Ultrasonic Doppler Speedometer]]===
Team members: Yang Yuzhen, Mi Tianshuo, Liu Xueyi, Shao Shuai

Design and build an ultrasonic Doppler speedometer to measure the velocity of a moving object.

==Resources==
===Books and links===
* A good textbook on the Physics of Sensors is Jacob Fraden: Handbook of Mondern Sensors, Springer, ISBN 978-3-319-19302-1 or [https://link.springer.com/book/10.1007/978-3-319-19303-8 doi:10.1007/978-3-319-19303-8]. There shoud be an e-book available through the NUS library at https://linc.nus.edu.sg/record=b3554643

===Software===
* Various Python extensions. [https://www.python.org Python] is a very powerful free programming language that runs on just about any computer platform. It is open source and completely free.
* [https://www.gnuplot.info Gnuplot]: A free and very mature data display tool that works on just about any platform used that produces excellent publication-grade eps and pdf figures. Can be also used in scripts. Open source and completely free.
* Matlab: Very common, good toolset also for formal mathematics, good graphics. Expensive. We may have a site license, but I am not sure how painful it is for us to get a license for this course. Ask if interested.
* Mathematica: More common among theroetical physicists, very good in formal maths, now with better numerics. Graphs are ok but can be a pain to make looking good. As with Matlab, we do have a campus license. Ask if interested.

===Apps===
Common mobile phones these days are equipped with an amazing toolchest of sensors. There are a few apps that allow you to access them directly, and turn your phone into a powerful sensor. Here some suggestions:

* Physics Toolbox sensor suite on [https://play.google.com/store/apps/details?id=com.chrystianvieyra.physicstoolboxsuite&hl=en_SG Google play store] or [https://apps.apple.com/us/app/physics-toolbox-sensor-suite/id1128914250 Apple App store].

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Photodiodes:
** Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
** Fast photodiodes (Silicon PIN, small area): [[Media:S5971_etc_kpin1025e.pdf|S5971/S5972/S5973]]
* PT 100 Temperature sensors based on platinum wire: [[Media:PT100_TABLA_R_T.pdf|Calibration table]]
* Thermistor type [[Media:Thermistor B57861S.pdf|B57861S]] (R0=10kΩ, B=3988Kelvin). Search for [https://en.wikipedia.org/wiki/Steinhart-Hart_equation Steinhart-Hart equation]. See [[Thermistor]] page here as well.
* Humidity sensor
** Sensirion device the reference unit: [[media:Sensirion SHT30-DIS.pdf|SHT30/31]]
* Thermopile detectors:
** [[Media:Thermopile_G-TPCO-035 TS418-1N426.pdf|G-TPCO-035 / TS418-1N426]]: Thermopile detector with a built-in optical bandpass filter for light around 4μm wavelength for CO2 absorption
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]
* Ultrasonic detectors:
** plastic detctor, 40 kHz, -74dB: [[Media:MCUSD16P40B12RO.pdf|MCUSD16P40B12RO]]
** metal casing/waterproof, 48 kHz, -90dB, [[Media:MCUSD14A48S09RS-30C.pdf|MCUSD14A48S09RS-30C]]
** metal casing, 40 kHz, sensitivity unknown, [[Media:MCUST16A40S12RO.pdf|MCUST16A40S12RO]]
** metal casing/waterproof, 300kHz, may need high voltage: [[Media:MCUSD13A300B09RS.pdf|MCUSD13A300B09RS]]
* Magnetic field sensor
** Fluxgate magnetometer [[media:Data-sheet FLC-100.pdf|FCL100]]
* Lasers
** Red laser diode [[media:HL6501MG.pdf|HL6501MG]]

==Some wiki reference materials==
* [https://www.mediawiki.org/wiki/Special:MyLanguage/Manual:FAQ MediaWiki FAQ]
* [[Writing mathematical expressions]]
* [[Uploading images and files]]

== Old Wiki ==
You can find entries to the wiki from [https://pc5271.org/PC5271_AY2324S2 AY2023/24 Sem 2]

Alcohol Concentration Measurement

2025-04-01T02:54:24Z

Chengrui:

Alcohol Concentration Measurement

2025-04-01T02:53:44Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Advantages of Infrared-Based Alcohol Detection ==

* '''Non-contact measurement''', reducing contamination.
* '''High accuracy''', based on alcohol-specific infrared absorption characteristics.
* '''Low cost''', with simple photodetection devices.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Alcohol Concentration Measurement

2025-04-01T02:51:08Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
This research proposes a non-contact alcohol concentration measurement method and infrared spectroscopy. This method measures changes in infrared light intensity transmitted through alcohol solutions, using photoelectric sensors and data fitting techniques to achieve high precision measurements.
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Alcohol Concentration Measurement

2025-04-01T02:49:53Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

== Objective ==
To determine the alcohol concentration in a sample solution by analyzing the absorption of light at a specific wavelength using an Oband light source and a photodetector.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Alcohol Concentration Measurement

2025-04-01T02:49:18Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Background ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Objective ==
To determine the alcohol concentration in a sample solution by analyzing the absorption of light at a specific wavelength using an Oband light source and a photodetector.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Alcohol Concentration Measurement

2025-04-01T02:48:16Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Overview ==
Alcohol (ethanol) is a widely used organic compound in medicine, chemical industry, food, and beverages. Rapid and accurate measurement of alcohol concentration is crucial in various industries, including food and beverage manufacturing, medical disinfection, and industrial synthesis. Existing measurement methods typically have limitations such as complexity, high equipment costs, and large measurement errors. Therefore, developing an efficient, cost-effective, and non-contact measurement method is essential.

[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Objective ==
To determine the alcohol concentration in a sample solution by analyzing the absorption of light at a specific wavelength using an Oband light source and a photodetector.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Alcohol Concentration Measurement

2025-04-01T02:46:41Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe, Sun Weijia, Yan Chengrui, Zhu Junyi

== Overview ==
This experiment aims to measure the concentration of alcohol in a solution using a light source (Oband) and a photodetector. The basic principle behind this setup is that the absorption of light by alcohol varies with concentration, and by measuring the intensity of light transmitted through the solution, we can determine the alcohol concentration.

[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Objective ==
To determine the alcohol concentration in a sample solution by analyzing the absorption of light at a specific wavelength using an Oband light source and a photodetector.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

Alcohol Concentration Measurement

2025-04-01T02:46:28Z

Chengrui:

= Experiment to Measure Alcohol Concentration Using Oband Light Source and a Photodetector =
== Team Member ==
Lim Gin Joe,Sun Weijia, Yan Chengrui, Zhu Junyi

== Overview ==
This experiment aims to measure the concentration of alcohol in a solution using a light source (Oband) and a photodetector. The basic principle behind this setup is that the absorption of light by alcohol varies with concentration, and by measuring the intensity of light transmitted through the solution, we can determine the alcohol concentration.

[[File:Transmittance-Diagram-1024x447.png|center|thumb|Schematic Diagram of the Experiment]]

== Objective ==
To determine the alcohol concentration in a sample solution by analyzing the absorption of light at a specific wavelength using an Oband light source and a photodetector.

== Equipment Required ==
* Oband Light Source: A broadband light source capable of emitting light across a spectrum of wavelengths.
* Photodetector: A device to measure the intensity of light that has passed through the sample solution.
* Alcohol Samples: Different alcohol solutions with known concentrations (e.g., ethanol, isopropanol).
* Cuvette: A transparent container to hold the alcohol solution for light transmission.
* Spectrometer: For recording and analyzing the intensity of transmitted light.
* Power Supply: To power the Oband light source.

== Methodology ==
=== 1. Setup the Apparatus ===
* Position the Oband Light Source: Place the Oband light source so that the emitted light can be directed towards the alcohol sample in the cuvette.
* Align the Photodetector: Position the photodetector on the opposite side of the cuvette to measure the intensity of light that passes through the alcohol solution.
* Cuvette Setup: Fill the cuvette with the alcohol sample. Ensure that the path of light through the cuvette is clear and that the cuvette is free from air bubbles.
* Ensure Proper Calibration: Before measuring the alcohol samples, calibrate the setup by using a solution of known concentration or distilled water to establish a baseline (zero absorption).

=== 2. Measure Absorbance ===
* Test Different Concentrations: Prepare alcohol samples of known concentrations. This will allow you to measure the light intensity passing through different levels of alcohol and correlate the intensity with the concentration.
* Record Light Intensity: For each sample, measure the light intensity that reaches the photodetector. Record the values using the spectrometer. Ensure to measure the intensity multiple times for each concentration to ensure accuracy.

=== 3. Analyze the Results ===
* Calculate Absorbance: Use the formula:
<math>
A = -\log \left( \frac{I}{I_0} \right)
</math>
where <math>A</math> is absorbance, <math>I_0</math> is the intensity of light from the Oband source, and <math>I</math> is the intensity of light received by the photodetector after passing through the alcohol solution.
* Plot the Absorbance vs Concentration: Create a graph to visualize the relationship between absorbance and alcohol concentration. The graph should show a linear or near-linear correlation.
* Determine the Alcohol Concentration: Using the absorption curve and the known concentration values, estimate the alcohol concentration of an unknown sample by comparing its absorbance value.

== Data Analysis ==
1. Beer-Lambert Law: The relationship between absorbance and concentration is governed by the Beer-Lambert Law, which states:
<math>
A = \epsilon \cdot c \cdot l
</math>
Where:
* <math>A</math> is the absorbance,
* <math>\epsilon</math> is the molar absorptivity (a constant for the alcohol),
* <math>c</math> is the concentration of the alcohol,
* <math>l</math> is the path length of light through the sample.

== References ==
* Beer-Lambert Law for Spectrophotometry
* Applications of Optical Sensing for Chemical Analysis
* Practical Guide to Spectrometer Calibration

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2025-02-14T05:53:34Z

Chengrui: /* Alcohol Concentration Measurement */