Patent ID: 8767128
Filing Date: 2014-07-01
Classification: G09G

Abstract:
1. An image display device comprising: a color display unit for displaying a color image; and a look-up table (LUT) which stores correction data for correcting color balance of the color image to be displayed on the color display unit, wherein when a color image based on input image data is displayed on the color display unit, an input signal value representing a brightness level of each color of red, green and blue in the input image data is corrected based on the correction data in the LUT so as to display a color image based on the corrected input signal value on the color display unit, and wherein the image display device further comprises: LUT correction data recalculating means for recalculating the correction data in the LUT based on the correction data; LUT correction data updating means for updating the correction data in the LUT to the correction data recalculated by the LUT correction data recalculating means; and gain adjusting means for providing gain to an adjustment input value which is an input signal value representing a brightness level of each color of red, green and blue in image data of a white balance adjustment image to be used for recalculating the correction data in the LUT, wherein when the adjustment image is displayed on the color display unit, the gain adjusting means provides a gain to the adjustment input value to generate a gain-modified adjustment input value, and the gain-modified adjustment input value is then corrected based on the correction data in the LUT so as to display a white balance adjustment image based on the corrected gain-modified input value, wherein a gain value, which is provided to the adjustment input value by the gain adjusting means and which brings color balance of the white balance adjustment image displayed on the color display unit to a predetermined color balance, is determined as an adjustment gain value, wherein the white balance adjustment image comprises a plurality of different white balance adjustment images, wherein the LUT correction data recalculating means recalculates the correction data in the LUT based on the correction data and the adjustment gain values for the plurality of white balance adjustment images, wherein the correction data in the LUT represents a relationship between a pre-correction value representing a pre-correction brightness level of each color of red, green and blue and a post-correction value representing a brightness level to be output after correcting the pre-correction value, wherein the number of the plurality of white balance adjustment images is two, wherein assuming that x denotes the pre-correction value, y=F(x) denotes the post-correction value before recalculation by the LUT correction data recalculating means, and further y=G(x) denotes the post-correction value after recalculation by the LUT correction data recalculating means, the LUT correction data recalculating means recalculates the post-correction value y=G(x) in the LUT as: where InL denotes the adjustment input value in image data of a Low side white balance adjustment image which is one of the two white balance adjustment images with a lower brightness level while InH denotes the adjustment input value in image data of a High side white balance adjustment image which is the other of the two white balance adjustment images with a higher brightness level, and where GainL denotes the adjustment gain value which brings color balance of the Low side white balance adjustment image to a predetermined color balance while GainH denotes the adjustment gain value which brings color balance of the High side white balance adjustment image to a predetermined color balance, and further where a denotes the quotient of (x−GainL)/(GainH−GainL).