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:
Jan. 15, 1991
Filed:
Mar. 22, 1990
Nobuyoshi Nagashima, Toenri, JP;
Toshio Matsumoto, Toenri, JP;
Shuhei Yasuda, Nara, JP;
Takafumi Kawaguchi, Nara, JP;
Makoto Takeda, Nara, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
The invention relates to a drive apparatus for a liquid crystal display device. The voltage, to be applied to longitudinally and latitudinally arranged liquid crystal cells of the liquid crystal display device, is altered in polarity from field to field and from frame to frame, whereby the occurrence of flicker is prevented. The field discriminating device counts the numbers of lines in first and second fields by synchronizing a vertical synchronizing signal at a leading point of a field time. Thereafter the difference in the number of lines between the first and second fields is detected, the field times being thereby discriminated. When a video signal is erroneous, the field discriminating device provides a field discriminating signal, the level of which is changed alternately from field time to field time.