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:
Dec. 11, 1990
Filed:
Sep. 18, 1989
Robert M Pleva, Livermore, CA (US);
Martin Randall, Santa Cruz, CA (US);
Chips and Technologies, Incorporated, San Jose, CA (US);
Abstract
The present invention provides a contrast enhancing method and circuit for mapping color signals into signals for driving a display which is capable of displaying shades of gray. With the present invention a preliminary translation is first made between a foreground-background color combination and the various shades of gray that can be displayed. The contrast or separation between the foreground level of gray and the background level of gray produced by this preliminary translation is then compared to parameters set by the operator. If the preliminary translation provides the desired degree of separation between the foreground and the background gray levels, no further translation takes place; however, if the desired degree of separaton was not achieved by the preliminary translation, the system forces further separation between the foreground and background by taking the following action: (a) if the background was darker than the foreground, the background is made still darker and/or the foreground is made still lighter (b) if the background was lighter than the foreground the background is made still lighter and/or the foreground is made still darker.