| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a lighting device which saves power without changing user's feeling to reaction of a proximity sensor.SOLUTION: The lighting device includes a light source 12, a proximity sensor 14 which emits an electromagnetic wave and detects a reflected electromagnetic wave resulting from reflection on an object of the emitted electromagnetic wave to output a detection signal indicative of detection of the reflected electromagnetic wave, and a control unit 13 which controls lighting and extinction of the light source on the basis of the detection signal. A period when the proximity sensor 14 emits the electromagnetic wave and detects the reflected electromagnetic wave is defined as a detection period, and a period when the proximity sensor 14 stops emission of the electromagnetic wave and does not detect the reflected electromagnetic wave is defined as a non-detection period. The control unit 13 controls the proximity sensor 14 so that the detection period and the non-detection period are alternately repeated while being a fixed time in total and the length of the detection period is varied in accordance with a state relating to detection of the proximity sensor 14.</p> |
