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:
Sep. 25, 1984
Filed:
Dec. 21, 1981
John K Cool, Thousand Oaks, CA (US);
Image Resource Corporation, Westlake Village, CA (US);
Abstract
Gamma correction in an imaging system which provides photographic reproductions of images represented by video signals is achieved by controlling the duration of exposure of a constant intensity scanning beam. A moving threshold signal is swept at a varying rate corresponding to a gamma correction curve between opposite limits over a given total exposure interval, as the image is repeatedly presented. The instantaneous amplitude of the video signal is compared to threshold signal and the results of the comparison used to control whether the beam is on or off for a given picture area. The gamma correction curves are advantageously presented as numerical sequences defining interlinked incremental segments of different slope.