IR Object Sensor

The IR receiver as a photodiode or a phototransistor is capable of detect infrared radiation emitted from the IR transmitter. Aesthetically it is similar to an LED but the external capsule can be wrapped by a dark color film. The IR transmitter sends an infrared signal that, in case of a reflecting surface (e.g. white color), bounces off in some directions including that of the IR receiver that captures the signal detecting the object. This result would occur even if the object is absent.