Patent ID: 9123280
Filing Date: 2015-09-01
Classification: G02F,G09G

Abstract:
1. An image display device with a function of controlling a backlight luminance, comprising: a display panel including a plurality of display elements configured or programmed to control light transmittances; a backlight including a plurality of light sources; an image divider configured or programmed to generate a plurality of input images by subjecting a plurality of images included in a plurality of frames of an externally provided video signal to either regional division within each frame or temporal division in units of a frame, or both; a plurality of luminance calculators configured or programmed to set a plurality of areas in accordance with the light sources for the plurality of input images, to process the plurality of input images in parallel on the basis of the input image for the set areas, to calculate emission luminance data specifying luminance upon emission of the light source corresponding to the areas, and to process the plurality of input images in parallel on the basis of the emission luminance data calculated for the areas and its predetermined surrounding areas, to calculate display luminance, which is luminance for display provided in the areas; a display data calculator configured or programmed to obtain display data to control the light transmittances of the display elements, on the basis of the input images and the display luminances obtained by the luminance calculators; a panel driver circuit configured to programmed to output signals to the display panel on the basis of the display data, said signals controlling the light transmittances of the display element; and a backlight driver circuit configured or programmed to output signals to the backlight on the basis of the emission luminance data, said signals controlling the luminances of the light sources, wherein, each of the luminance calculators is configured or programmed to receive other emission luminance data calculated by the other luminance calculators or values used to calculate said other emission luminance data, and calculate the display luminance on the basis of the received other emission luminance data or values, the image divider is configured or programmed to generate a plurality of input images through regional division within each frame after the image included in the video signal is temporally divided in units of a frame, the plurality of luminance calculators include: when the emission luminance data calculated by a corresponding emission luminance calculator changes from other emission luminance data calculated by another emission luminance calculator for an immediately previous input image and the change is greater than or equal to a predetermined threshold, the display luminance calculator is configured or programmed to calculate the display luminance on the basis of emission luminance data obtained by subtracting a predetermined amount less than the threshold from the other emission luminance data.