The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 16, 1990
Filed:
Feb. 28, 1989
Applicant:
Inventor:
Richard L McMaster, Pittsford, NY (US);
Assignee:
Detection Systems, Inc., Fairport, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01J / ;
U.S. Cl.
CPC ...
250349 ; 250342 ;
Abstract
A dual channel intrusion detection system comprising first and second radiation sensors. Each sensor has a pair of elements viewing adjacent zones of the protected area, the zones being slightly offset from each other in the direction of expected intruder movement. Sequence detection is provided for producing an intruder-present signal in response to simultaneous actuation of one element of each sensor when preceded by actuation of the other element of one of the sensors. Additional immunity from false triggering is obtainable if this sequence must be followed by actuation of the other element of the second sensor.