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:
Aug. 16, 1994
Filed:
Jul. 29, 1992
Applicant:
Inventors:
William A Lagoni, Indianapolis, IN (US);
Ronald T Keen, Indianapolis, IN (US);
Charles B Neal, Zionsville, IN (US);
Assignee:
Thomson Consumer Electronics, Inc., Indianapolis, IN (US);
Primary Examiner:
Int. Cl.
CPC ...
H04N / ;
U.S. Cl.
CPC ...
348673 ; 348695 ;
Abstract
A video input signal to be displayed is applied to an offset clamp circuit which effects a DC offset of blanking and active video portions of each video line. The DC offset or shift is of an amount and in a polarity sense to place the black level of the active portion of an NTSC color standard signal at a level corresponding to blanking level of the NTSC color standard. Advantageously, subsequent clamping at the shifted level enables contrast control without altering the black level of displayed images.