In-cell capacitive touch panel

摘要

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.