Patent · US Expired

Intrusion detection system using three pyroelectric sensors

US4943800A · kind A · utility

22Cited by
6References
11Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 17, 1988
Grant dateJul 24, 1990
Priority date
Expiry dateJun 17, 2008

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S250/01
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

The intrusion detection system of the invention, in which three pyroelectric detectors are disposed in line with a interval and an adjoining two of the three pyroelectric detectors are electrically connected to cancel electrical charges generated by each pyroelectric detector, detects intrusion of an infrared ray radiating object such as a human body for example by output signals outputted from the adjoining two and the other of the three pyroelectric detectors or by output signals outputted from the pyroelectric detector disposed at the center and adjoining one and output signals outputted from the one disposed at the center and adjoining another one of these pyroelectric detectors, so that precise and secure intrusion detection is possible by reducing erroneous signals generated by those pyroelectric detectors due to variation of the atmospheric temperature and the like.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.