Se-Ki Park

64.4: Smart Algorithms for Local Dimming LED Backlight

To reduce power consumption and improve image quality including contrast ratio and color gamut, LED backlight units (BLUs) consisting of many small blocks in 2-dimensional space are implemented. Either white-gray-level luminance or color is controlled by the local dimming LED BLU. However, such a BLU can induce various recognizable artifacts. A method is proposed for exact block luminance calculation along with a new algorithm to correct local dimming artifacts. A new concept of color classes has also been developed to achieve extremely wide color gamut and to minimize color related artifacts.

48.4: Invited Paper: Adaptive Luminance and Power Control (ALPC) for LED Backlight Units

Adaptive luminance and power control is proposed for LCD-TVs with LED backlight units to provide several advanced features compared to conventional local dimming LED backlights. with ALPC, the luminance of a bright image on the display increases as the size of the bright image decreases, resulting in higher image quality that is more comfortable to end users. A 46” FHD LCD-TV equipped with an ALPC LED backlight achieved peak luminance of 500 nits and a contrast ratio of 100,000:1 with 30% fewer LEDs and maximum power consumption of 100W.