Patent ID: 8810501

Claim:
A backlight control system for controlling a backlight of a display, the display comprising: a transmissive display panel; and a backlight configured to provide an illumination to a backside of the display panel, the backlight comprising a plurality of respective light sources positioned at respective predetermined light source positions for providing illumination to respective overlapping portions of the backside of the display panel according to respective predetermined light source luminance profiles, wherein an intensity of the light source luminance profile is scalable by means of a light source drive value, and wherein a superposition of the respective scaled light source luminance profiles defines a backlight profile; the backlight control system comprising: a drive value generator configured to provide the light source drive values in dependence on image luminance values corresponding to an image to be displayed by the display, the image comprising a high luminance image portion having a higher luminance than that of an area around the high luminance image portion, the drive value generator being further configured to cause the backlight profile to gradually descend around a high luminance portion of the display on which the high luminance image portion is displayed at a rate that is independent of a position of the high luminance portion with respect to the light source positions, the high luminance portion of the display having a higher luminance than an area around the high luminance portion of the display, wherein the drive value generator is further configured to emulate virtual light sources at each pixel positions of the high luminance portion of the display so that each pixel of the display at the high luminance portion of the display has a virtual light source.