 Photoresistor Also known as: Photocell, electric eye Description: A photoresistor is an electronic component that changes its resistance
depending upon how much light it is exposed to at any given moment. Uses: Photoresistors are used to sense when it is dark outside in order to turn
on electric outdoor lighting. They can be used to detect the position of
objects placed in front of them that are blocking a light source. Facts: Photoresistors are commonly made out of cadmium sulfide (CdS). Cadmium
sulfide is a semiconductor that more readily conducts electricity when
light is present. The more light, the less the resistance. Photoresistors
have a longer response time to changes in light levels than alternative
light detectors such as phototransistors. |
