With a base area that is sensitive to light, phototransistors are semiconductor devices that are either bi-terminal (emitter and collector) or tri-terminal (emitter, base, and collector).

PN-junction diodes that use light energy to generate an electric current are known as photodiodes. They go by the names photo-detector, light detector, and photo-sensor as well. The reverse bias condition is intended to operate in photodiodes.

In the depletion area, the absorbed photons form electron-hole pairs. Photo detectors include, among others, photodiodes and photo transistors. A portion of the absorbed light energy is converted into electrical energy by solar cells.

A visible or infrared light beam is released by a photoelectric sensor from its light-emitting device. To find the light beam reflected from the target, a reflective-type photoelectric sensor is employed. The amount of light that changes as a target crosses the optical axis is measured using a thrubeam type sensor.

Yes, since the phototransistor adjusts the current in response to changes in the intensity of the light. Despite having just two terminals, I consider the phototransistor to be a variable resistor.

In the field of photoelectric conversion, bipolar phototransistors are crucial because they have a higher optical responsivity than photodiodes. The potential benefits of heterogeneous integration and good optical responsiveness are provided by two-dimensional materials, but mass production is challenging.

A semiconductor called a photodiode is used to transform light energy into an electrical current. On the other hand, light energy is converted into an electrical current by the phototransistor using a transistor. The photodiode generates both the voltage and the current, while the phototransistor just produces the current.

The Photoresistor (Analog Input) IntroductionAn LDR (light-dependent resistor) is another name for it.

A photoresistive/photoconductive device is a light-dependent resistor. Popular devices for photojunction are photodiodes and phototransistor.

Bipolar junction transistors that incorporate a photodiode junction are known as phototransistor types. The photocurrent generated at the base-collector junction of an NPN phototransistor serves as the base current IB.