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:
Jul. 26, 1983
Filed:
Dec. 07, 1981
Applicant:
Inventor:
Mahmoud A Hamamsy, Watchung, NJ (US);
Assignee:
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02B / ;
U.S. Cl.
CPC ...
250551 ; 307311 ;
Abstract
A normally-OFF switch includes a transistor branch path and a parallel pair of oppositely poled thyristor branch paths to protect against voltage surges. To minimize latching-on of the thyristors as a result of voltage surges, the thyristor branch paths including light emitting diodes which light up when excess current flows in the thyristor branch paths and actuate a photodiode array which biases the transistor path to conduction to divert excess current from the thyristor path.