SIGNAL CONVERSION CIRCUIT, AND MULTIPLE PRIMARY COLOR LIQUID CRYSTAL DISPLAY DEVICE HAVING THE CIRCUIT

摘要

There is provided a signal conversion circuit which is suitably used in a multiprimary liquid crystal display device (especially a multiprimary liquid crystal display device which performs display in a vertical alignment mode), and a multiprimary liquid crystal display device having such a signal conversion circuit. A signal conversion circuit according to the present invention is for use in a multiprimary liquid crystal display device which performs display in a vertical alignment mode, and converts an input video signal to a multiprimary signal corresponding to four or more primary colors. When generating a multiprimary signal for displaying dark skin, the signal conversion circuit according to the present invention applies a conversion to the video signal so that a color difference ”u'v'=((u'-u60') 2 +(v'-v 60 ') 2 ) is 0.03 or less, the color difference ”u'v' being defined by CIE1976 chromaticity coordinates (u', v') representing a chromaticity when the pixel is viewed from the frontal direction and CIE1976 chromaticity coordinates (u 60 ', v 60 ') representing a chromaticity when the pixel is viewed from a 60° oblique direction.