| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a detecting device which can maintain its guarding ability by detecting the maneuvering action taken by an invader with an intention of making the detector unable to detect the invader. SOLUTION: A detecting device is constituted by combining a plurality of sets of detecting elements 3 constituted of thermopiles and light condensing optical systems 2 of lenses, etc., with each other and detects an invader into an area to be watched, such as the room, etc., by dividing the area into a plurality of detecting areas. Each detecting element 3 outputs the voltage corresponding to the absolute temperature based on an invader who invades into the area to be watched. A processing means 6 detects the invader based on the changes of the voltage outputs of the detecting elements 3, but, when the voltage outputs of the elements 3 become nearly equal to each other, discriminates that the invader takes such a maneuvering action that provides a barrier in front of the detecting area of the detecting device so as to make the device unable to detect the invader and outputs the corresponding maneuvering action detecting signal.</p> |
