| 摘要 |
<p>The present invention causes noise in a low-luminance portion to become less prominent when a backlight is divided into a plurality of regions and the luminance of the backlight is controlled in accordance with a video signal corresponding to each of the regions. An area active control portion (2) divides a video signal into a plurality of regions and outputs a first feature amount for every region. An LED control portion (3) determines a first luminance for each of the divided regions of an LED backlight (5) in accordance with the first feature amount of every region. Within a range where the total value of an LED drive current is no greater than a predetermined allowable current value, a magnification constant is uniformly multiplied by the first luminance to determine a second luminance. The second luminance and a threshold value are compared, and, only with respect to those regions where the second luminance is lower than the threshold value, the second luminance is again lowered to make a third luminance. The third luminance and also the second luminance of the regions where the second luminance has not been lowered are used to control the LED light emission in each of the divided regions.</p> |
