What is a Photoelectric Sensor?

A photoelectric sensor basically emits light from a transmitter, which contains a light-emitting element. The receiver at the other end will detect this light beam. When this emitted light is intercepted by any object, the intensity of the beam of light received by the receiver changes. The intensity of the light is continuously processed and converted into an electrical output. As the intensity varies, the electric output varies. This electrical output is then fed to any circuit and indicates whether or not any object has passed between the lights. This is the concept of the photoelectric sensor.