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. 20, 1998
Filed:
Aug. 01, 1996
Sharp Kabushiki Kaisha, Osaka, JP;
Abstract
During a display period (Y-coordinate detection period), an image is written to an electro-optical material so as to form a display by driving row electrodes and column electrodes by using a row-electrode driving circuit and a column-electrode driving circuit so as to selectively operate TFTs. In this case, a shift data signal having a width corresponding to two clocks of a horizontal sync signal is supplied to the row-electrode driving circuit by using a start-pulse-width expanding circuit; therefore, two row-electrode scanning signals are simultaneously inputted to two of the corresponding row electrodes. Moreover, the row-electrode scanning signals have periods in which they instantaneously turn 'off' respectively, and the turning-off timing is coincident in the respective signals. Since a Y-coordinate detection signal is detected in this manner, it becomes possible to increase an induced voltage to be exerted in a detection electrode of an electronic pen, to improve the S/N ratio of the Y-coordinate detection signal, and also to enhance the detection accuracy of the Y-coordinate.