Patent ID: 8842138
Filing Date: 2014-09-23
Classification: G09G

Abstract:
1. A liquid crystal display, comprising: a liquid crystal panel; a backlight unit that supplies light to the liquid crystal panel and has a plurality of light sources; and an image calibration unit that calculates a global dimming resultant value and a local dimming resultant value for an image data signal inputted to the liquid crystal panel, analyzes an average picture level for each block with respect to the image data signal, and determines a convex combination parameter based on the global dimming resultant value, the local dimming resultant value, and the average picture level to generate a calibration dimming value for the backlight unit and an image calibration value for the image data signal, wherein the calibration dimming value is defined in the following equation: where ‘dim(i, j)’ refers to a dimming value of the backlight unit, ‘dimGD’ refers to the degree of the driven backlight unit upon global dimming, ‘dimLD(i, j)’ refers to the degree of the driven backlight unit according to the position of a light source upon local dimming, and ‘a’ has a relationship as follows: 0<a<1, whereby the calibration dimming value is a mixing of the global and local dimming resultant values, wherein the image calibration unit calculates the average picture level and analyzes a difference value in the average picture level between neighboring blocks, wherein the image calibration unit increases a weight value for the global dimming resultant value when the difference value in the average picture level between the neighboring blocks is large, and the image calibration unit increases a weight value for the local dimming resultant value when the difference value of the average picture level between the neighboring blocks is small.