Patent ID: 7944429

Claim:
A liquid crystal display device, comprising: a liquid crystal panel divided into a non-display area and a display area where pixel cells are arranged in a matrix wherein the non-display area is in the periphery of the display area; a gate driver mounted on a first tape carrier package for supplying a gate signal to the liquid crystal panel; a data driver mounted on a second tape carrier package for supplying a data signal to the liquid crystal panel; a backlight for supplying light to the liquid crystal panel; and a photo-sensing device in the non-display area for sensing an external light to control light output from the backlight in accordance with the sensed external light, wherein the photo-sensing device is formed in the non-display area of a thin film transistor array substrate of the liquid crystal panel, wherein the photo-sensing device is on a portion of the thin film transistor array substrate that is not overlapped by the color filter array substrate, wherein the photo-sensing device has a structure in which a plurality of parallel connected thin film transistors are configured to commonly share a gate electrode, a plurality of drain electrodes, a plurality of source electrodes and a semiconductor pattern such as their channels acts as a light receiving part of the photo-sensing device, wherein a path of photo current flows to the drain electrodes through the plurality of channels from the source electrodes of the photo-sensing device in accordance with the received light amount, wherein the photo-sensing device further comprises a source line connected to the source electrode of the photo-sensing device and a drain line connected to the drain electrode of the photo-sensing device, wherein the first and second tape carrier packages include a first output pad connected to the gate electrode of the photo-sensing device, a second output pad connected to the source line and a third output pad connected the drain line, wherein a first driving voltage is supplied to the gate electrode of the photo-sensing device through the first output pad from a separate voltage source for driving the photo-sensing device, the source line receives a second driving voltage from the separate voltage source through the second output pad for driving the photo-sensing device, the drain line supplies the sensing voltage sensed by the photo-sensing device to the third output pad.