Photo Resistor

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Photo Resistor


A photo resistor (Light Dependent Resistor, LDR) is a light-dependent resistance of an amorphous semiconductor layer. The higher the incidence of light is smaller because of the internal photoelectric effect, its electrical resistance. Photo sensors are only on the sensitivity of the photomultiplier surpassed, however, react very slowly (range 1 ms to several seconds).

A photo-resistance is a component whose value depends on the light ohms to which it is exposed (Sze, p. 50 - 90). It also means the LDR (Light Dependent Resistor = light dependent resistor).


A photoresistor is composed of a semiconductor high resistivity. If the incident light ...