Patent ID: 7460103
Filing Date: 2008-12-02
Classification: G09G

Abstract:
1. A video display apparatus having a light modulation device for forming a picture in accordance with a video signal, a lighting unit for irradiating, on said light modulation device, illumination light necessary to cause it to display the picture, and a light diffusing layer for diffusing the illumination light from said lighting unit, said lighting unit being divided into n light source partitive areas which are controllable in luminance individually, said apparatus comprising: a maximum luminance distribution detecting circuit for calculating a maximum luminance distribution on the screen from video signals; an illumination light source luminance setting circuit for setting illumination luminance levels of said individual illumination light source partitive areas on the basis of the result of calculation by said maximum luminance distribution detection circuit; an illumination light source luminance control circuit for controlling the luminance levels of said individual illumination light source partitive areas on the basis of illumination light source luminance setting values of said individual partitive areas set by said illumination light source luminance setting circuit; a light diffusing layer luminance distribution calculating circuit for calculating a luminance distribution on said light diffusing layer on the basis of the illumination light source luminance setting values of said individual partitive areas set by said illumination light source luminance setting circuit; and video signal correction means for correcting the video signal on the basis of the result of luminance calculation by said light diffusing layer luminance distribution calculating circuit.