Patent ID: 8289265

Claim:
A backlight controller, comprising: a temporal weighting module, calculating a weight sum of a first backlight luminance provided in a current frame and a target backlight luminance to serve as an adjusted backlight luminance, which equal to L1Ã—W+L2Ã—(1âˆ’W), only when the variation of the target backlight luminance in comparison with the backlight luminance of the immediate previous image frame exceeds a predetermined range, wherein L1 is the target backlight luminance, L2 is the first backlight luminance, W is a reference weight which equals to a gray scale average of the image content of the current frame divided by the maximum gray scale level of an image frame, and the target backlight luminance is obtained from analyzing the statistics of an image content of the current frame; and a dimming controlling module, coupled to the temporal weighting module for increasing or decreasing the adjusted backlight luminance by a step value of the target backlight luminance, and thereby generating a second backlight luminance provided in a next frame.