Patent ID: 8184107
Filing Date: 2012-05-22
Classification: G02F

Abstract:
1. A liquid crystal display comprising: a liquid crystal display panel including a plurality of pixels each having a touch sensor circuit; a transparent conductive layer on an first substrate of the liquid crystal display panel transmitting display light; an insulating layer on the transparent conductive layer; a sensing circuit to generate a touch or non-touch sensing signal based on changes in the amount of surface charge of the transparent conductive layer depending on whether or not the insulating layer is touched; a driving voltage supply circuit to change the level of a driving voltage required to drive the touch sensor circuit inside the pixel depending on the touch or non-touch sensing signal; a readout IC to convert a light sensing signal received from a plurality of readout lines into a digital signal; and a system to perform a touch algorithm based on the digital signal, wherein the driving voltage of a high potential for a light sensing operation of the touch sensor circuit is generated only when the touch or non-touch sensing signal indicates that the insulating layer is touched, and wherein the touch sensor circuit includes a sensor TFT to generate a light current only when the driving voltage has the high potential, a sensor capacitor to store charges generated by the light current, and a switch TFT to supply the charges stored in the sensor capacitor to the readout lines as the light sensing signal.