Name the device which converts the change in intensity of illumination to change in electric current flowing through it. Plot I-V characteristics of this device for different intensities. State any two applications of this device.
Answer
Photodiodes are used to detect optical signals of different intensities by changing current flowing through them.
I-V Characteristics of a photodiode
Applications of photodiodes:
- In detection of optical signals.
- In demodulation of optical signals.
- In light operated switches .
- In speed reading of computer punched cards.
- In electronic counters
