One of the major differences between the photodiode and the phototransistor is that the photodiode uses a PN junction diode that converts the light energy into electrical current while the phototransistor uses the ordinary transistor (NPN transistor) to convert light into electricity.
Major Difference between Photodiode and Phototransistor:-
- The phototransistor generates power while the photodiode generates both voltage and current.
- The response of the photodiode is much faster than the phototransistor.
- The photodiode is a semiconductor device that converts the energy of light into electricity. While the phototransistor uses the transistor to convert light energy into electricity.
- The photodiode is less sensitive than the phototransistor because the phototransistor generates the large output current.
- The photodiode is used in solar power plants, in a photometer, etc., while the phototransistor is used to detect the light.
- The photodiode operates in both the forward and reverse directions while the phototransistor operates in the forward direction.
- The emitter of the phototransistor is negative compared to the collector region.