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:
Oct. 22, 1991
Filed:
Sep. 22, 1989
Kazuo Sekiya, Tokyo, JP;
Yuichi Shiraishi, Yamato, JP;
International Business Machines Corporation, Armonk, NY (US);
Abstract
A display system for converting first gray level signals of N bits/dot each, representing 2.sup.N gray levels, to second gray level signals of M bits/dot each, representing 2.sup.M gray levels, where N is an integer larger than or equal to 2 and M is an integer satisfying N>M.gtoreq.1, by separating each of the first gray level signals of N bits into higher M bits and lower N-M bits and respectively using the N-M bit values to select an appropriate table from among 2.sup.N-M tables, each of which stores a distinctive set of P.times.Q modification values satisfying P.times.Q.gtoreq.2.sup.N-M, then respectively adding the M bits and each of the modification values of said selected table to generate P.times.Q second gray level signals, and supplying the resulting second gray level signals to a display device of 2.sup.M gray levels. The first gray level signals may be supplied to a display device of 2.sup.N gray levels having a smaller number of display dots than the display device of 2.sup.M gray levels.