PC5271 wiki - User contributions [en]

LEDs as Photodiodes

2024-04-27T15:34:23Z

Abassyahbana: /* Equipment */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resistor, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, there are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We varied the applied voltage on the emitter (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7 V) and measured the corresponding current on the emitter. We also set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver using an oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
#Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).
#3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863873.pdf
#3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863874.pdf

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:33:02Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resistor, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, there are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We varied the applied voltage on the emitter (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7 V) and measured the corresponding current on the emitter. We also set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver using an oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
#Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).
#3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863873.pdf
#3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863874.pdf

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:31:08Z

Abassyahbana: /* References */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resistor, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We varied the applied voltage on the emitter (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7 V) and measured the corresponding current on the emitter. We also set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver using an oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
#Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).
#3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863873.pdf
#3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863874.pdf

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:30:27Z

Abassyahbana: /* References */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resistor, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We varied the applied voltage on the emitter (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7 V) and measured the corresponding current on the emitter. We also set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver using an oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
:Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).
:3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863873.pdf
:3mm Round LED Lamp [Datasheet]. U.S. Multicomp Pro. https://www.farnell.com/datasheets/2863874.pdf

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:26:12Z

Abassyahbana: /* Experimental Setup */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resistor, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We varied the applied voltage on the emitter (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7 V) and measured the corresponding current on the emitter. We also set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver using an oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:25:15Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We varied the applied voltage on the emitter (3, 3.5, 4, 4.5, 5, 5.5, 6, 6.5, and 7 V) and measured the corresponding current on the emitter. We also set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver using an oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:16:24Z

Abassyahbana: /* Introduction */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the Light-Emitting Diode (LED), there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:15:14Z

Abassyahbana: /* Logbook */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanches.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanches.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:14:01Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). We set the voltage for the receiver to be 5 V and recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:12:21Z

Abassyahbana: /* Equipment */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors (1k and 100k)
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:11:25Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We used the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:11:00Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. From their datasheet, the applied voltage has a somewhat linear relation with forward current. Moreover, forward current has a linear relation with relative luminous intensity of the emitter. Thus, setting the applied voltage for the emitter means somewhat setting the light intensity of the emitter as well.

We use the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T15:09:33Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

We also tried other LEDs with knowing part numbers (703-0090 and 703-0091) from the Multicom Pro. We use the same type of LEDs as the emitter and the receiver. As shown below, the photocurrent produced from 703-0091 is bigger that the photocurrent produced from 703-0090. When we checked the datasheets of these LEDs, we noticed that the power dissipation of 703-0091 is 72 mW, bigger that the power dissipation of 703-0090 (66 mW). We predict that there is a relation between the photocurrent produced and the power dissipation.

{| class="wikitable"
| [[File:Two led.png|500px|thumb|left|Photocurrent produced versus the current of the emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T14:54:07Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the photocurrent on the receiver showed in the oscilloscope. By knowing the photocurrent on the receiver and measuring the current on the emitter, we can produce some graphs shown below.

We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T14:46:40Z

Abassyahbana: /* Experimental Setup */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED corresponds to the certain choice of voltage. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the intensity showed in the oscilloscope. We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T14:43:36Z

Abassyahbana: /* Results and Discussion */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the intensity showed in the oscilloscope. We controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T14:43:16Z

Abassyahbana: /* Experimental Setup */

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Schematic2.png|500px|thumb|left|The schematic of the setup]]
|}

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the intensity showed in the oscilloscope. We Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

File:Schematic2.png

2024-04-27T14:42:15Z

Abassyahbana:

LEDs as Photodiodes

2024-04-27T14:08:09Z

Abassyahbana:

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
For the experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscilloscope, we could detect the signals.

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. There are some LEDs that we used as emitter and receiver such as transparent 5 mm red LED (R5t), 5 mm green LED (G5), 3 mm blue LED (B3), 5 mm red LED (R5), 3 mm orange LED (O3), and 5 mm orange LED (O5). Then recorded the intensity showed in the oscilloscope. We Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5 mV. However, we also discovered that some special LED pairs can reach the voltage about 20 mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

{| class="wikitable"
| [[File:R5t.png|500px|thumb|left|R5t as the receiver with various kinds of emitter]]
| [[File:R5.png|500px|thumb|left|R5 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:G5.png|500px|thumb|left|G5 as the receiver with various kinds of emitter]]
| [[File:B3.png|500px|thumb|left|B3 as the receiver with various kinds of emitter]]
|}
{| class="wikitable"
| [[File:O3.png|500px|thumb|left|O3 as the receiver with various kinds of emitter]]
| [[File:O5.png|500px|thumb|left|O5 as the receiver with various kinds of emitter]]
|}

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T13:57:09Z

Abassyahbana:

LEDs as Photodiodes

2024-04-27T13:53:30Z

Abassyahbana:

== Group Members ==
Abas Syahbana, Lu Xinghao

== Introduction ==
In the LED, there is a region called the depletion region. Photons outside the LED can fall to this region. Photons with greater energy than the energy gap of the semiconductor that composes the LED will be absorbed and produce electron-hole pairs. Then, a current is produced caused by the electric field across the region that pulls those pairs. This resulting current, called photocurrent, is proportional to the number of photons that fall to the depletion region.

{| class="wikitable"
| [[File:LED1.png|700px|thumb|left|(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent]]
|}

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
In this project, ....
According to the specific experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscillograph, we could detect the signals

{| class="wikitable"
| [[File:Exp2.jpeg|500px|thumb|left|Experimental setup (close-up view)]]
| [[File:Exp3.jpeg|500px|thumb|left|Experimental setup (wide view)]]
|}

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. Then recorded the intensity showed in the oscillograph. Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5mV. However, we also discovered that some special LED pairs can reach the voltage about 20mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

[[image: B3.png|500px]] [[image: G5.png|500px]]
[[image: O3.png|500px]] [[image: O5.png|500px]]
[[image: R5.png|500px]] [[image: R5t.png|500px]]
[[image: Two led.png|500px]]

== References ==
Schirripa Spagnolo, G., Leccese, F., & Leccisi, M. (2019). LED as Transmitter and Receiver of Light: A Simple Tool to Demonstration Photoelectric Effect. Crystals, 9(10).

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

File:Exp3.jpeg

2024-04-27T13:50:10Z

Abassyahbana: Experimental setup (wide view)

== Summary ==
Experimental setup (wide view)

File:Exp2.jpeg

2024-04-27T13:48:40Z

Abassyahbana: Experimental Setup

== Summary ==
Experimental Setup

LEDs as Photodiodes

2024-04-27T13:45:18Z

Abassyahbana: /* References */

LEDs as Photodiodes

2024-04-27T13:35:41Z

Abassyahbana:

LEDs as Photodiodes

2024-04-27T13:27:09Z

Abassyahbana: /* Introduction */

File:LED1.png

2024-04-27T13:24:27Z

Abassyahbana: (a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent

== Summary ==
(a) Electron-hole pairs produced by absorption of photons (b) Band diagram of LED when photocurrent produced (c) Illustration of the flow of the photocurrent

LEDs as Photodiodes

2024-04-27T13:22:01Z

Abassyahbana: /* Introduction */

LEDs as Photodiodes

2024-04-27T13:12:48Z

Abassyahbana: /* Introduction */

LEDs as Photodiodes

2024-04-27T05:10:03Z

Abassyahbana: /* Introduction */

== Group Members ==
Abas Syahbana, Lu Xinghaou

== Introduction ==
Explanation of howe photodiodes work and how LEDs as Photodiodes work.

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
In this project, ....
According to the specific experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscillograph, we could detect the signals.

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. Then recorded the intensity showed in the oscillograph. Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5mV. However, we also discovered that some special LED pairs can reach the voltage about 20mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

== References ==
PhysicsOpenLab. (2020) “Using LED as a single photon detector”. PhysicsOpenLab. https://physicsopenlab.org/2020/02/27/using-led-as-a-single-photon-detector/

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T04:55:54Z

Abassyahbana:

== Group Members ==
Abas Syahbana, Lu Xinghaou

== Introduction ==
The principle behind using LEDs as single photon detectors lies in their ability to exhibit a phenomenon known as avalanche multiplication. This phenomenon occurs when a single photon interacts with the semiconductor material within the LED, triggering a cascade of electron-hole pairs via the process of impact ionization. 1.Photon Absorption: When a single photon of sufficient energy strikes the semiconductor material of the LED, it can excite an electron from the valence band to the conduction band, creating an electron-hole pair. 2.Impact Ionization: The newly generated electron can gain enough energy to cause further excitations within the semiconductor material through impact ionization. This process leads to the creation of additional electron-hole pairs. 3.Avalanche Effect: If the conditions are right, meaning the electric field within the LED is sufficiently strong, these newly generated electron-hole pairs can also undergo impact ionization, leading to a cascade effect where the number of charge carriers rapidly increases. 4.Detecting the Avalanche: The avalanche of charge carriers results in a measurable current pulse that can be detected by external circuitry connected to the LED. By measuring this current pulse, it's possible to infer the presence of a single photon that initiated the avalanche. 4.Sensitivity and Efficiency: The sensitivity and efficiency of LED-based single photon detectors depend on various factors, including the semiconductor material used, the design of the LED structure, the applied bias voltage, and the temperature. Optimizing these parameters is crucial for maximizing the detector's performance.

== Setup ==

=== Equipment ===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

=== Experimental Setup ===
In this project, ....
According to the specific experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscillograph, we could detect the signals.

== Results and Discussion ==
In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. Then recorded the intensity showed in the oscillograph. Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5mV. However, we also discovered that some special LED pairs can reach the voltage about 20mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

== References ==
PhysicsOpenLab. (2020) “Using LED as a single photon detector”. PhysicsOpenLab. https://physicsopenlab.org/2020/02/27/using-led-as-a-single-photon-detector/

== Logbook ==
5 March 2024: we took variety of LEDs in the workshop. We detected avalanche.

7 March 2024: We tried all of the LEDs. almost all of them can not detect avalanche.

12 March 2024: We tried other variety of LEDs from the workshop. we can not see any detection of avalanche. Then, we knew that we use LEDs in unconventional way.

14 March 2024: We didn't see any detection. We plan to use function generator to see any detection.

19 March 2024: We used function generator to see the signal. We didn't see anything.

21 March 2024: We saw something that can be a signal with frequency of the function generator f=1858 Hz. We planned to use battery to lessen the noise.

26 March 2024: We were somehow doing the experiment wrongly. It was using battery for the transmitter and trying detecting avalanche

28 March 2024: We changed the power source of the receiver to battery. We still didn't get rid of the noise.

2 April 2024: We can see the difference in signal. However we need bigger sensing resistor to measure it better.

4 April 2024: We can detect the signal. Then, we changed the function generator with a power source for the transmitter. We started measuring all of the combination of LEDs as the emitter and the receiver.

9 April 2024: We continued measuring all of the combination with 10x probe. We didn't use some LEDs that cannot detect light as receiver.

11 April 2024: We completed the measurement of the combination of 5 different LEDs as emitter and receiver.

16 April 2024: We measured the same type of LEDs as the emitter and receiver. We also measured the current at the emitter

18 April 2024: We finished measuring the same type of LEDs as the emitter and receiver and the current at the emitter.

LEDs as Photodiodes

2024-04-27T04:31:07Z

Abassyahbana:

LEDs as Photodiodes

2024-04-27T04:21:00Z

Abassyahbana: /* Group Members */

Abas Syahbana, Lu Xinghaou

Main Page

2024-04-27T04:14:28Z

Abassyahbana: /* Photodiodes as Single Photon Detectors */

'''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.

<span style="color:red">Deadline for editing reports is <b>Saturday, 27 April, 23:59SGT</b></span> - Make sure your description is ready by then so we can start assessing it :)

==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.

===[[Simple Optical Heart Rate Monitor]]===
This project demonstrates the principles of photoplethysmography (PPG) through the construction of a simple device to measure heart rate. The project involves using an pulse sensor to detect variations in light absorption caused by changes in blood volume during each heartbeat.

===[[Gas sensor]]===
This project aims to use high and low detection methods of tin dioxide (SnO2) sensor to detect carbon monoxide or other combustible gases.

===[[Optical Sensor for Noise Flickering]]===
Group Members: Eric Cheung; Lee An Min, Amanda; Loh Jia Ying Whitney

This project aims to use a simple voltage divider made up with resistors and LDR to measure visual noise tags.

===[[Real time temperature alarm ]]===

This project aims to build a system using Python and Raspberry Pi to measure and display temperature in real-time using temperature sensors, and to issue an alarm when the temperature exceeds the set threshold

===[[Impedance Spectroscopy for Detecting Phase Transitions in KBr]]===

This project aims to use Impedance spectroscopy as a sensor to detect phase transition in Potassium Bromide (KBr).

===[[Sensor for locating sound sources]]===
A microphone array is used to capture sound signals, and the direction of the sound source is determined by analyzing the time difference of sound signals received by different microphones.

===[[Optical Sensor for UV Radiation]]===
This project aims to design a photodiode-based optical sensor to detect UV radiation levels.

===[[High Sensitive Position Sensor based on PDH technique]]===

Group Members: Angela Anna Baiju, Chenyue Gu

This project uses PDH locking technique to align a cavity to its resonance and read out the error signal to analyse the position change and other noises present in the system.

===[[LEDs as Photodiodes]]===
Group Members: Abas Syahbana, Lu Xinghaou

In this project, we will use several LEDs as Photodiodes. When an LED receive light, it produces signal that we can detect. We will see the relation between currents that represent the signal and currents for the light source.

===[[Temperature Sensor]]===
This project aims to construct a portable non-contact thermometer to detect the component temperature after the circuit board is energized, thereby preventing burns from direct contact.

===[[Quartz Crystal MicroBalance (QCM)]]===
This project aims to create a quartz crystal microbalance that can measure small masses (on the order of micrograms and below) for a start. The bigger goal would be to create one that can detect the thicknesses of thin films.

==Resources==
===Recorded sessions===
===Devices and material===
Apart form the stuff in the teaching lab, we have a resources you may want to consider for your project:
*...
===Books and links===
===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.

===Data sheets===
A number of components might be useful for several groups. Some common data sheets are here:
* Generic Silicon pin Photodiode type [[Media:Bpw34.pdf|BPW34]]
* Digital microphone [https://www.knowles.com/docs/default-source/default-document-library/sph0655lm4h-1_cornell_ii_datasheet9e1e1c731dff6ddbb37cff0000940c19.pdf SPH0655LM4H-1]; a small adapter board exists (see [[Soldering small parts]])
* 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.
* Resistor color codes are explained [https://en.wikipedia.org/wiki/Electronic_color_code here]

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

Photodiodes as Single Photon Detectors

2024-04-27T04:04:05Z

Abassyahbana: /* Doing experiment */

In this project, we use several photodiodes as Single Photon Avalanche Detectors (SPADs). We use a light bulb as the light source and grating to vary the wavelength of the light source. We will build a passive quenching configuration to get photons detected. Thus, by knowing which light source is working for the LEDs to detect photons, we can determine band gaps of each LEDs.

==Setup==
===Equipment===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

===Circuit Overview===
===Software===
==Procedure==
===Basic theory===
The principle behind using LEDs as single photon detectors lies in their ability to exhibit a phenomenon known as avalanche multiplication. This phenomenon occurs when a single photon interacts with the semiconductor material within the LED, triggering a cascade of electron-hole pairs via the process of impact ionization.
1.Photon Absorption: When a single photon of sufficient energy strikes the semiconductor material of the LED, it can excite an electron from the valence band to the conduction band, creating an electron-hole pair. 2.Impact Ionization: The newly generated electron can gain enough energy to cause further excitations within the semiconductor material through impact ionization. This process leads to the creation of additional electron-hole pairs. 3.Avalanche Effect: If the conditions are right, meaning the electric field within the LED is sufficiently strong, these newly generated electron-hole pairs can also undergo impact ionization, leading to a cascade effect where the number of charge carriers rapidly increases. 4.Detecting the Avalanche: The avalanche of charge carriers results in a measurable current pulse that can be detected by external circuitry connected to the LED. By measuring this current pulse, it's possible to infer the presence of a single photon that initiated the avalanche. 4.Sensitivity and Efficiency: The sensitivity and efficiency of LED-based single photon detectors depend on various factors, including the semiconductor material used, the design of the LED structure, the applied bias voltage, and the temperature. Optimizing these parameters is crucial for maximizing the detector's performance.
===Doing experiment===
According to the specific experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscillograph, we could detect the signals.

In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. Then recorded the intensity showed in the oscillograph. Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5mV. However, we also discovered that some special LED pairs can reach the voltage about 20mV, which is far large than the others. We thought that situation was very interesting and tried to identify the inner relation between them.

===Results===

==Analyse==
===Data taking===

===Data analysis===

==Reference==

Photodiodes as Single Photon Detectors

2024-04-27T04:02:46Z

Abassyahbana: /* Equipment */

In this project, we use several photodiodes as Single Photon Avalanche Detectors (SPADs). We use a light bulb as the light source and grating to vary the wavelength of the light source. We will build a passive quenching configuration to get photons detected. Thus, by knowing which light source is working for the LEDs to detect photons, we can determine band gaps of each LEDs.

==Setup==
===Equipment===
:Power Source
:Arduino Uno
:Resistors
:Breadboard
:Jump wires
:Variety of LEDs
:Oscilloscope
:Probe

===Circuit Overview===
===Software===
==Procedure==
===Basic theory===
The principle behind using LEDs as single photon detectors lies in their ability to exhibit a phenomenon known as avalanche multiplication. This phenomenon occurs when a single photon interacts with the semiconductor material within the LED, triggering a cascade of electron-hole pairs via the process of impact ionization.
1.Photon Absorption: When a single photon of sufficient energy strikes the semiconductor material of the LED, it can excite an electron from the valence band to the conduction band, creating an electron-hole pair. 2.Impact Ionization: The newly generated electron can gain enough energy to cause further excitations within the semiconductor material through impact ionization. This process leads to the creation of additional electron-hole pairs. 3.Avalanche Effect: If the conditions are right, meaning the electric field within the LED is sufficiently strong, these newly generated electron-hole pairs can also undergo impact ionization, leading to a cascade effect where the number of charge carriers rapidly increases. 4.Detecting the Avalanche: The avalanche of charge carriers results in a measurable current pulse that can be detected by external circuitry connected to the LED. By measuring this current pulse, it's possible to infer the presence of a single photon that initiated the avalanche. 4.Sensitivity and Efficiency: The sensitivity and efficiency of LED-based single photon detectors depend on various factors, including the semiconductor material used, the design of the LED structure, the applied bias voltage, and the temperature. Optimizing these parameters is crucial for maximizing the detector's performance.
===Doing experiment===
According to the specific experiment, we have designed two circuits. One of them was emitting circuit and the other one was receiving circuit. For the emitting circuit, we also used LED as the light source. By changing the voltage applied to that LED, we can control the intensity of emission. As the same time, we also measured the current through LED. For the receiving part, we also used LED to receive the light. However, by reversing the direction of LED, which would response to different wavelengths of light and produced the current. Then, by measuring the voltage of the resister, which was series connected in the circuit through oscillograph, we could detect the signals.

In the experiment, we have used 4 different colors red, blue, green and orange served as emitter color and receiver color separately. Then recorded the intensity showed in the oscillograph. Controlled the other parameters and concentrated just on the color. Mostly the voltage of signal we found are only around 0.5mV. However, we also discovered that some special LED pairs can reach the voltage about 20mV, which is far large than the others. I thought that situation was very interesting and tried to identify the inner relation between them.

===Results===

==Analyse==
===Data taking===

===Data analysis===

==Reference==

Photodiodes as Single Photon Detectors

2024-02-22T03:36:50Z

Abassyahbana: /* Equipment */

Photodiodes as Single Photon Detectors

2024-02-22T03:36:38Z

Abassyahbana: /* Equipment */

Photodiodes as Single Photon Detectors

2024-02-22T03:36:27Z

Abassyahbana: /* Equipment */

Photodiodes as Single Photon Detectors

2024-02-22T03:36:04Z

Abassyahbana:

Photodiodes as Single Photon Detectors

2024-02-22T03:25:12Z

Abassyahbana: Created page with "In this project, we use several photodiodes as Single Photon Avalanche Detectors (SPADs). We use a light bulb as the light source and grating to vary the wavelength of the light source. We will build a passive quenching configuration to get photons detected. Thus, by knowing which light source is working for the LEDs to detect photons, we can determine band gaps of each LEDs."

Main Page

2024-02-22T03:17:22Z

Abassyahbana: /* LEDs as Single Photon Detectors */

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.

===[[Simple Optical Heart Rate Monitor]]===
This project demonstrates the principles of photoplethysmography (PPG) through the construction of a simple device to measure heart rate. The project involves using an LED and photodiode to detect variations in light absorption caused by changes in blood volume during each heartbeat.

===[[Gas sensor]]===
This project aims to use high and low detection methods of tin dioxide (SnO2) sensor to detect carbon monoxide or other combustible gases.

===[[Optical Sensor for Noise Flickering]]===
Group Members: Eric Cheung; Lee An Min, Amanda; Loh Jia Ying Whitney

This project aims to use a simple voltage divider made up with resistors and LDR to measure visual noise tags.

===[[Real time temperature alarm ]]===

This project aims to build a system using Python and Raspberry Pi to measure and display temperature in real-time using temperature sensors, and to issue an alarm when the temperature exceeds the set threshold

===[[Gravitational Torsion Balance]]===

This project aims to determine the gravitational constant using the gravitational torsion balance based on the Cavendish Experiment

===[[Sensor that recognizes specific sounds and steers toward the source]]===
A microphone array is used to capture sound signals, and the direction of the sound source is determined by analyzing the time difference of sound signals received by different microphones.

===[[Optical Sensor for UV Radiation]]===
This project aims to design a photodiode-based optical sensor to detect UV radiation levels.

===[[High Sensitive Position Sensor based on PDH technique]]===

Group Members: Angela Anna Baiju, Chenyue Gu, Joel K Jose

This project uses PDH locking technique to align a cavity to its resonance and read out the error signal to analyse the position change and other noises present in the system.

===[[Photodiodes as Single Photon Detectors]]===
Group Members: Abas Syahbana, Lu Xinghaou

In this project, we will use several LEDs as Single Photon Avalanche Detectors (SPADs). We will use a light bulb as the light source and grating to vary the wavelength of the light source. Thus, by knowing which light source is working for the LEDs to detect photons, we can determine band gaps of each LEDs.

==Resources==
===Recorded sessions===
===Devices and material===
Apart form the stuff in the teaching lab, we have a resources you may want to consider for your project:
*...
===Books and links===
===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.

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

Main Page

2024-02-22T03:11:39Z

Abassyahbana:

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.

===[[Simple Optical Heart Rate Monitor]]===
This project demonstrates the principles of photoplethysmography (PPG) through the construction of a simple device to measure heart rate. The project involves using an LED and photodiode to detect variations in light absorption caused by changes in blood volume during each heartbeat.

===[[Gas sensor]]===
This project aims to use high and low detection methods of tin dioxide (SnO2) sensor to detect carbon monoxide or other combustible gases.

===[[Optical Sensor for Noise Flickering]]===
Group Members: Eric Cheung; Lee An Min, Amanda; Loh Jia Ying Whitney

This project aims to use a simple voltage divider made up with resistors and LDR to measure visual noise tags.

===[[Real time temperature alarm ]]===

This project aims to build a system using Python and Raspberry Pi to measure and display temperature in real-time using temperature sensors, and to issue an alarm when the temperature exceeds the set threshold

===[[Gravitational Torsion Balance]]===

This project aims to determine the gravitational constant using the gravitational torsion balance based on the Cavendish Experiment

===[[Sensor that recognizes specific sounds and steers toward the source]]===
A microphone array is used to capture sound signals, and the direction of the sound source is determined by analyzing the time difference of sound signals received by different microphones.

===[[Optical Sensor for UV Radiation]]===
This project aims to design a photodiode-based optical sensor to detect UV radiation levels.

===[[High Sensitive Position Sensor based on PDH technique]]===

Group Members: Angela Anna Baiju, Chenyue Gu, Joel K Jose

This project uses PDH locking technique to align a cavity to its resonance and read out the error signal to analyse the position change and other noises present in the system.

===[[LEDs as Single Photon Detectors]]===
Group Members: Abas Syahbana, Lu Xinghaou

In this project, we will use several LEDs as Single Photon Avalanche Detector (SPAD). We will use a light bulb as the light source and grating to vary the wavelength of the light source. Thus, by knowing which light source is working for the LEDs to detect photons, we can determine band gaps of each LEDs.

==Resources==
===Recorded sessions===
===Devices and material===
Apart form the stuff in the teaching lab, we have a resources you may want to consider for your project:
*...
===Books and links===
===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.

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