Dual channel pyroelectric intrusion detector
US4614938A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | May 21, 1984 |
| Grant date | Sep 30, 1986 |
| Priority date | — |
| Expiry date | May 21, 2004 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S250/01
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
An intrusion detection system includes a plurality of infrared radiation sensitive elements, each of which comprises first and second spaced electrodes between which polarized pyroelectric material is positioned, each element being operative to produce a voltage proportional to the rate of change of infrared radiation incident thereon. The elements are closely spaced to one another and cover substantially all of at least one surface of the pyroelectric material. Multiple fields of view of areas under surveillance are fully covered (with negligibly small gaps). Alternate sensor elements are connected to a first amplifier channel and the other sensor elements are connected to a second amplifier channel. Coincidence means produces an alarm output in response to concurrent intruder signal generation by both of the amplifier channels.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.