A local dimming algorithm for low power LCD TVs using edge-type LED backlight

A local dimming algorithm is proposed to reduce the power consumption of LCD TVs using edge-type LED backlight. The proposed local dimming algorithm is implemented by matrix driving of orthogonally located LEDs at the edge of the backlight. The dimming rate of LED string is determined according to target luminance of local blocks and modified to reduce image distortion. The backlight power saving ratios of four typical images are 23.2-53.2 % and 30.2- 54.3% by using proposed division and rate algorithms, respectively. PSNR is greater than 48 dB using proposed local dimming algorithms.