| 摘要 |
PROBLEM TO BE SOLVED: To highly precisely detect an object to be detected across the wide range of environmental illuminance.SOLUTION: Each of a plurality of detection circuits U generates a detection signal S corresponding to the presence/absence of a detected object. The plurality of detection circuits U are divided into a plurality of first detection circuits U1 and a plurality of second detection circuits U2 with the different ranges of sensible illuminance. A driving circuit 20 selectively executes a first detecting operation to obtain the detection signal S by driving the plurality of first detection circuits U1 in each unit period UP and a second detecting operation to obtain the detection signal S by driving the plurality of second detection circuits U2 in each unit period PU, according to environmental illuminance. |
