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. 13, 1994
Filed:
Nov. 12, 1992
Applicant:
Inventors:
Johannes A Van Haaren, Eindhoven, NL;
Franciscus J Blommaert, Eindhoven, NL;
Antonius G Verhulst, Eindhoven, NL;
Assignee:
U.S. Philips Corporation, New York, NY (US);
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G02F / ; G02F / ;
U.S. Cl.
CPC ...
359254 ; 359245 ; 359320 ; 359 87 ; 345 55 ; 345 89 ;
Abstract
In a bistable switching display device the occurrence of artefacts due to considerable changes of periodicity between successive grey scale stages is reduced by a suitable subdivision of the electrodes (112). To this end a drive unit (116) allocates fewer than 2.sup.n grey scale stages to each pixel (113) which is subdivided into n sub-pixels (113.sup.a, 113.sup.b, 113.sup.c). The change of periodicity will decrease when a suitable division of the surface ratios and drive sequence are chosen.