Patent ID: 8427418

Claim:
A liquid crystal display comprising: a liquid crystal display panel; a backlight unit including a plurality of light sources, the backlight unit providing light to the liquid crystal display panel; a backlight driving circuit that individually drives a plurality of previously determined blocks each including the light sources based on a dimming value of each of the blocks; and a local dimming control circuit that calculates a pixel gain value compensating for a luminance reduction resulting from the dimming value of each block and corrects the pixel gain value based on a grayscale saturation level of each block, wherein the local dimming control circuit adjusts a first light amount indicating an amount of light reaching each pixel when all of the light sources are turned on at a constant brightness and corrects the pixel gain value, wherein the local dimming control circuit includes: an image analysis unit that analyzes an input data of each block to obtain a representative value of each block; a dimming value determining unit that maps the representative value of each block to a previously determined dimming curve to determine the dimming value of each block; a light amount obtaining unit that obtains the first light amount and a second light amount indicating an amount of light reaching each pixel in local dimming using the dimming value of each block; a gain value calculating unit that calculates the pixel gain value of each pixel based on the first and second light amounts; a data modulation unit that multiplies the input data by the pixel gain value to compensate for the input data; and a gain value correcting unit that analyzes the compensated input data to generate an estimate value of the grayscale saturation level and adjusts the first light amount based on the estimate value of the grayscale saturation level to perform a feedback process to the gain value calculating unit.