WORKING PRINCIPLE

This consist of two devices; a light emitter and a light receiver. These two devices are kept apart facing each other. The Gallium-Aluminium-Arsenide-Luminescent diode integrated in the transmitter sends pulses of light in the infra-red range which are invisible to the human eye. The receiver opposite to the transmitter receive these rays. Sensing is achieved when these rays are interrupted by the object.

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