Patent ID: 8049711

Claim:
A liquid crystal display device, comprising: an LCD panel modulating light transmissivities of plural pixels disposed in a matrix form on the basis of respective gradation data; an illumination device for irradiating light to the respective pixels while a ratio (duty ratio) of a lighting time in one frame period is changed; and a display data conversion part for calculating respective lightnesses and a lightness histogram from the respective gradation data, determining a threshold lightness from the lightness histogram on the basis of a previously determined ratio of pixels to be saturated in brightness, processing the respective gradation data on the basis of the threshold lightness to output them to the LCD panel, and outputting duty ratio data to change the duty ratio to the illumination device, wherein the display data conversion part counts the lightnesses from the lightness histogram in descending order of lightness on the basis of the ratio of the pixels to be saturated in brightness and determines the threshold lightness.