Patent ID: 8264451

Claim:
A display panel control device for controlling a display panel and a back-face light source which configures a plurality of light source blocks formed on a back face of the display panel in parallel to a line sequential scanning direction, the control device comprising: a black image insertion driving part which starts video display scanning and black or dark image display scanning for the display panel, and performs black or dark image insertion drive in a specific period; and a light-up timing control part which sets and controls a light-up and a light-off start timing of each of the plurality of light source blocks, based on a synchronous signal that synchronizes with a timing for starting the video display scanning or a timing for starting black or dark image display scanning performed by the black image insertion part, wherein the light-up timing control part controls the setting of the light-up start timing or the light-off start timing so as to satisfy a period condition wherein a light-off period of a given light source block becomes equal to or less than a period from an end of the black or dark image display scanning on all display lines within a block area of the display panel corresponding to a given light source block to a start of the video scanning on the first display line within the block area, wherein, provided that driven line number of the display panel is “Vtotal”, scanning line number that is display line number of the display panel is “Vdisp”, dividing number of the divided light source blocks is “N”, a black image insertion rate in a frame period by the black image insertion driving part is “Xp”, and a light-off rate that is a ratio of the light-off period in the frame period is “Xb”, the light-up timing control part performs controls based on the light-off period and the number of blocks set according to the black image insertion rate, by satisfying a co-relational condition between the black image insertion rate Xp and the light-off rate Xb expressed as follows: Xb≦XP −( V disp/ N )/ V total.