| 摘要 |
PROBLEM TO BE SOLVED: To prevent each lighting device from performing incorrect detection in a lighting system wherein a plurality of lighting devices having active radio wave type human-sensitive sensors are provided. SOLUTION: Zero-cross detection sections for detecting a zero-cross point of an AC power source AC are provided in respective lighting devices A, B, C forming the lighting system, and the respective lighting devices A, B, C are synchronized each other on the basis of the zero-cross point. Then, sensor sections 3 of respective lighting devices A, B, C operate for a designated time T<SB>0</SB>only from a point of time having elapsed designated delay times t<SB>A</SB>, t<SB>B</SB>, t<SB>C</SB>from the point of time of zero cross point. Thus, the radio wave transmitted from the different lighting device is not received since the sensor sections 3 of respective lighting devices A, B, C are not simultaneously operated, and respective lighting devices A, B, C are difficult to cause incorrect detection. COPYRIGHT: (C)2011,JPO&INPIT |
