CRIME PREVENTION DEVICE AND LUMINAIRE

摘要

PROBLEM TO BE SOLVED: To provide a crime prevention device which makes an alarm sound easy to hear even in the presence of ambient noise without making an output sound loud, and a luminaire.

SOLUTION: When ambient lightness detected by a lightness sensor part 3 decreases below a specified threshold level, a control part 1 turns on a light source part 4 and when a person sensor part 2 detects a person staying in a detection area in this state, the control part outputs two sounds differing in frequency alternately from a sound output part 5 with nearly the same sound volume at specified time intervals for a specified time and also the light source part 4 is blinked in synchronism with frequency change of the output sounds.

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