As the fan blades spin they disrupt the beam of infrared light between the emitter and the receiver ... You won’t be limited to an IR sensor, but can use a hall effect sensor in the same ...

Photoelectric sensors use light to sense the presence, absence, or distance of target objects. They consist of an emitter light source, a photodiode or phototransistor receiver, and supporting ...

Forward scatter sensors include an emitter and receiver. They emit an infrared light beam at an offset angle from the receiver. The amount of light scattered by particles in the air and received by ...

The receiver also has sockets for several IR emitters (IR flashers) that are wired to, and pasted directly over, the IR sensors for precise aiming. High-end, third-party remote controls use radio ...