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:
May. 14, 2013
Filed:
Mar. 17, 2009
Po-yang Chen, Taipei, TW;
Po-sheng Shih, Taipei, TW;
Kei-hsiung Yang, Taipei, TW;
Hannstar Display Corporation, Taipei, TW;
Abstract
An in-cell capacitive touch panel is disclosed. The present invention utilizes a sensing unit that comprises a sensing liquid crystal capacitor and three transistors to detect touch events. A first transistor is connected to a first gate line and the sensing liquid crystal capacitor and controlled by the first gate line to charge the sensing liquid crystal capacitor. A second transistor together with a third transistor functions as a capacitance-current converter. The second transistor generates an output current according to the voltage of a first electrode of the sensing liquid crystal capacitor. A second gate line controls the third transistor to transfer the output current through a readout line to a readout unit that determines the touch positions. Thus, the in-cell capacitive touch panel of the present invention can use a simple-structure readout circuit to achieve superior readout accuracy and is adaptive to various sizes of touch panels.