| 摘要 |
PROBLEM TO BE SOLVED: To balance the light receiving state between two light receiving units of a light beam type detector configured of: a light projector housing two light projection units; and a light receiver housing two light receiving units, wherein a detection signal is generated when light receiving signals of the two light receiving units are lowered simultaneously down to the detection signal generation level. SOLUTION: A received light quantity output unit is disposed in each of the light receiving units of the light receiver, for individually receiving infrared modulated light from each of the light projecting units of the corresponding light projector and for outputting the received light level. In the light receiver, a readjustment warning means is disposed, for reading the received light level of the received light quantity output unit of each of the light receiving units and for prompting readjustment if there is a light receiving unit which does not reach a preset received light level. COPYRIGHT: (C)2010,JPO&INPIT |
