Patent ID: 8154533

Claim:
A liquid crystal display device comprising: a liquid crystal panel including a plurality of pixels connected to gate lines and data lines thereon, respectively; a gate drive circuit applying scan signals to the gate lines; a data drive circuit applying pixel voltage signals to the data lines; at least one sensor unit formed in at least one pixel region and sensing external lights and a touch of the liquid crystal panel; a switch unit switching a switch voltage and the pixel voltage signals to be applied to the data lines on the liquid crystal panel; a sense processor processing the sensed signal from the sensor unit; and a timing controller controlling the gate drive circuit, the data drive circuit, the switch unit, and the sense processor to be driven in one of data write mode and light sense mode, wherein the sense unit includes a sense element sensing the external lights and the touch of the liquid crystal panel; a read-out line transferring the sensed signal from the sense element to the sense processor; and a thin film transistor, responsive to a control signal, switching the sensed signal to be applied from the sense element to the read-out line, wherein the read-out line and the data line are simultaneously precharged with the switch voltage during the light sense mode.