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. 04, 1983
Filed:
Oct. 17, 1979
Applicant:
Inventor:
Henri Hodara, Altadena, CA (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G08B / ; G08B / ;
U.S. Cl.
CPC ...
340550 ; 250215 ; 250221 ; 340545 ; 340555 ; 350 961 ; 350 9634 ;
Abstract
A transparent continuous optical fiber is embedded in a transparent panel made of glass or plastic, with the two ends of the fiber accessible from outside the panel for coupling to a visible or invisible light source and detector respectively. By nearly matching the refractive indices of the panel and the fiber, and using good-quality material for the fiber so that it does not scatter significant amounts of the light passing through it, the fiber can be made virtually invisible although it establishes a complete light circuit. Cutting or breaking through the panel at a point intersecting the fiber interrupts the light circuit and triggers an alarm.