Question
Mon November 14, 2011 By:

How do photo transistor work?

Expert Reply
Tue November 15, 2011
The phototransistor is similar to a normal transistor which has a base, emitter and a couple. However in a phototransistor the base is the amount of light falling on it. As more light falls on the substrate the resistance of the phototransistor changes
In a phototransistor, more light results in more electrons moving to the base and therefore a bigger current.
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