| 摘要 |
<p>PURPOSE:To make it unnecessary to detect the presence of people in the whole room and to reduce the number of sensors by detecting the moving direction of the object to be detected on the basis of detecting signals from a plurality of sensors. CONSTITUTION:The presence/absence of an object 2 is detected by a plurality of infrared sensors 1 aligned in the advancing direction with a predetermined distance at the ceiling or the wall near the entrance of a room. These sensors are characteristic of the large detecting angle in a perpendicular direction to the aligning direction. In other words, the changing direction of output signals of the detecting sensors 1 is detected by a direction detecting/controlling part 5, whereby it is detected whether a person enters the room or goes out of the room. The number of persons in the room is counted at an entry/leave managing/controlling part 7. A predetermined time later after the last person leaves the room, the apparatus is turned OFF. Accordingly, the number of sensors can be reduced even for a large room.</p> |
