ILLUMINATION LIGHT TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To provide an illumination light transmission system capable of preventing collision of data transmitted being superimposed on illumination light from a plurality of lighting fixtures independently of the environment under which the lighting fixtures are installed.

SOLUTION: A control circuit 2 allows a time count circuit 7 to start counting a prescribed delay time ST from a point of time when the control circuit 2 receives a zero cross point detection signal from a zero cross point detection circuit 6 and the control circuit 2 superimposes transmission data outputted from a signal source 1 on illumination light when counting the delay btime STis complete by the time count circuit 7. Since the lighting fixtures T apply time division multiplex transmission to the transmission data while taking synchronization at zero cross points of a commercial AC power supply, it is not required to provide a light receiving means for receiving the illumination light to each lighting fixture unlike prior arts and it is prevented that the data transmitted superimposed on the illumination light from the lighting fixtures T collide with each other and cannot normally be received by a receiver R independently of the environment under which lighting fixtures are installed.

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