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:
Mar. 11, 1997
Filed:
Dec. 19, 1995
Applicant:
Inventors:
Goro Ueda, Tokyo, JP;
Hiroshi Shiba, Tokyo, JP;
Assignee:
NEC Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
348676 ; 348674 ;
Abstract
A gamma correcting circuit has a plurality of differential amplifiers having respective input terminals for being supplied with a video signal and respective output terminals connected in common. At least one of the differential amplifiers comprises differential pairs of transistors including transistors whose bases are not connected to the input terminal, emitters are connected to respective resistors, and collectors are connected in common. A plurality of individually energizable and de-energizable external reference voltage supplies are connected to the bases of the transistors whose bases are not connected to the input terminal.