| 摘要 |
<p>An object of the present invention is to provide a passive infrared detector which can surely discriminate an intruder and a small animal passing proximately to the detector without detracting the performance for detecting the intruder within the guard coverage area (alert object area). According to the present invention, there is provided a passive infrared detector for detecting a moving object such as intruder comprising an optical unit having a PCB (print circuit board) disposed in front of a base and mounted thereon a plurality of lenses vertically arranged at predetermined spaces and detecting elements arranged at positions corresponding to the lenses, and a control means for processing signals detected by the detecting elements characterized in that the spaces between the plurality of lenses are set so that they are small for a size of a human body and large for a size of a small animal, and that the control means are adapted to judge whether the moving object is an intruder or a small animal by discriminating the simultaneity of signals detected by the detecting elements or by summing the detected signals.</p> |
