Patent ID: 8139022

Claim:
A liquid crystal display device comprising: a liquid crystal panel configured to display an image from image signals; a backlight device disposed on the back side of the liquid crystal panel, and divided into regions, the backlight device comprising light sources in the respective regions, the light sources positioned to emit light into the liquid crystal panel, and the backlight device configured so that light emitted from each light source of each region leaks into adjacent regions; a maximum gradation detector configured to detect, at predetermined intervals, a maximum gradation of each regional image signal displayed on regions of the liquid crystal panel that correspond to the regions of the backlight device; an emission luminance calculator configured to obtain, from the maximum gradation, a light luminance for each light source; a luminance bitmap memory configured to hold a luminance bitmap that indicates luminance distribution characteristics of the liquid crystal panel, which shows the distribution of luminance of light emitted from the light source in the region of this light source, and in regions other than the region of this light source, the luminance bitmap including data that correspond to each pixel in the image signal; an image gain calculator configured to determine a gain to multiply an image signal for display on an arbitrary point in each region of the liquid crystal panel, the gain is an inverse of a value obtained by gamma correction on an integral value of light, each value obtained by multiplying the luminance of light that each light source emits, calculated by the emission luminance calculator, from data corresponding to the arbitrary point in the luminance bitmap, the gain has a value that differs depending on the position of each region of the liquid crystal panel, the gain calculated on the basis of the luminance bitmap and the luminance of light that each light source emits, the luminance obtained by the emission luminance calculator, the image gain calculator obtains the gain in correspondence with each pixel of the image signal; and a multiplier configured to multiply an image signal for display on each region by the gain obtained by the image gain calculator, and to output the image signal for display on the liquid crystal panel.