Patent ID: 8400395
Filing Date: 2013-03-19
Classification: H05B

Abstract:
1. A machine-implemented method of controlling local dimming of a plurality of light sources each corresponding to a respective light source block, where each light source block provides backlighting for an associated plurality of image regions, the method comprising: (a) initially determining first respective duty ratios for respectively driving a first of the light sources and a second of the light sources, where the first and second of the light sources neighbor one another, where said initial determining uses a first target luminance value of a first image region that is closest to the first light source and a second target luminance value of a second image region that is closest to the second light source, and where the initial determining thereby establishes the first respective duty ratios as current respective duty ratios; (b) second determining if the combination of the established current respective duty ratios expectedly provide sufficient minimal backlighting for a third image region to support a corresponding third target luminance value of the third image region, and if not adjusting the current respective duty ratios to thereby increase the expected backlighting for a third image region, where the adjusting is based on a difference between the third target luminance value and the expected contribution from the first and second light sources when driven in accordance with the pre-adjustment current respective duty ratios; and (c) driving the first and second first light sources in accordance with the first respective duty ratios if the second determining determines that the first respective duty ratios are sufficient,