| 摘要 |
<p>PROBLEM TO BE SOLVED: To realize at low cost a monitor which detects an invader to a monitoring region by detecting the change of brightness in a specific monitoring region and prevents erroneous operation by exterior light variations. SOLUTION: A monitor 1 provided with light reception parts 20 and 30 detecting light quantity by taking in the light from a monitoring region and an environmental light reception part 40 taking in only the light from the surroundings of the monitoring region and detecting the light quantity judges the invasion into the monitoring region by the light quantity variation detected with the light reception parts 20 and 30 using a light quantity variation operation part 13. When invasion is judged, a camera drive circuit 14 is operated and imaging of the monitoring region is executed with a camera 50.</p> |
