Infrared intruder detection system
US4704533A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1986 |
| Grant date | Nov 3, 1987 |
| Priority date | — |
| Expiry date | Apr 8, 2006 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S250/01
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
An infrared intruder detection system has two separate channels A and B. Each channel has its own pyroelectric detector device and threshold level comparator. The comparator is responsive to dual polarity pyroelectric voltage outputs produced by the associated detector device as a result of an intruder-related infrared image moving thereacross. A logic circuit analyzes the comparator outputs and responds to the identification of particular intruder-indicative sequences of comparator outputs in both channels to generate an alarm and/or switching output. The logic circuit may also identify shock-induced comparator outputs. The system offers a high intruder detection capability with immunity from false triggering.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.