What is a Phototransistors?Phototransistor DefinitionA phototransistor is defined as a semiconductor device with a light-sensitive base region, designed specifically for detecting and amplifying light signals.Phototransistors are semiconductor devices with either three terminals (emitter, base, and collector) or two terminals (emitter and collector) and have a light-sensitive base region. While all transistors are somewhat light-sensitive, phototransistors are specifically optimized for light de