Patent ID: 8896618

Claim:
A liquid crystal display device comprising: a liquid crystal panel including a plurality of display blocks and adapted to display an image in response to image signals; a plurality of light-emitting blocks adapted to emit light to the liquid crystal panel and corresponding to the plurality of display blocks; a first look-up table including a normalized value; and a timing controller adapted to receive the normalized value corresponding to each of the light-emitting blocks from the first look-up table and use the normalized value to provide an optical data signal corresponding to each of the light-emitting blocks, wherein the normalized value is obtained by dividing an initial duty ratio corresponding to a brightness value by a duty ratio corresponding to a maximum gray level, wherein the timing controller determines an initial brightness of each of the light-emitting blocks corresponding to the image signal, and determines an amplitude of the optical data signal on the basis of a ratio of the low-brightness light-emitting blocks, wherein the ratio of the low-brightness light-emitting blocks corresponds to a ratio of a number of low-brightness light-emitting blocks having an initial brightness that is lower than a reference brightness to a number of high-brightness light-emitting blocks having an initial brightness that is higher than the reference brightness among the plurality of light-emitting blocks, and wherein: the amplitude of the optical data signal is increased according to the ratio of the low-brightness light-emitting blocks, if the ratio of the low-brightness light-emitting blocks is more than a reference ratio; and the amplitude of the optical data signal is maintained without any change, if the ratio of the low-brightness light-emitting blocks is less than the reference ratio.