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:
Jan. 25, 1994
Filed:
Dec. 22, 1992
E Peter Anderson, Redwood City, CA (US);
James A Ashford, San Carlos, CA (US);
Richard Klass, Stevenville, MI (US);
Scientific Technologies Incorporated, Hayward, CA (US);
Abstract
A method of operation of a light curtain system for sensing the intrusion of objects into detection planes which define a protected zone. A group of light beams are strobed from one transmitter in a first direction across a zone to a receiver, and another group of light beams are strobed from another transmitter across the zone to another receiver. Light beams within each group which intersect a desired entry area are deactivated for penetration of a permitted object, and other beams in the groups are enabled to detect intrusion into the objects in portions of the zone which lie around the entry area.