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:
Aug. 31, 2004
Filed:
Oct. 04, 2001
Toshihiro Yanagi, Taki-gun, JP;
Kouji Kumada, Tenri, JP;
Takashige Ohta, Yamatokoriyama, JP;
Katsuya Mizukata, Shijonawate, JP;
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
An active matrix liquid crystal display drives liquid crystal by writing through TFTs, etc. a source signal from a signal line drive circuit to display electrodes in display cells on a matrix substrate and applying a common signal supplied from a common signal generator to common electrodes on an opposite substrate, the common signal changing in polarity in each frame. After scanning is completed for scan lines corresponding to one frame, a controller controls the interval between scan periods and the cycle of change in polarity of the common signal so as to provide a non-scan period that is longer than the scan period. The provision of the non-scan period extends the duration in which a specified voltage is retained by the display cell. This reduces the effects of variations in retained voltages caused by parasitic capacitance which develops in reflective electrode structures in which the display electrodes partly overlook scan lines and signal lines. Thus, in frame inversion drive, differences in brightness between the top and bottom of the display screen are reduced, and display quality is improved.