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Local Dimming Design for LCD Backlight

  • Shih-Chang HsiaEmail author
  • Xin-Yan Jiang
  • Shag-Kai Wang
Conference paper
  • 485 Downloads
Part of the Communications in Computer and Information Science book series (CCIS, volume 1013)

Abstract

The local-dimming backlight has recently been presented for use in LCD TVs. However, the image resolution is low, particularly at weak edges. In this work, a local-dimming backlight is developed to improve the image contrast and reduce power dissipation. The algorithm enhances low-level edge information to improve the perceived image resolution. Based on the algorithm, a 42-in. backlight module with white LED (Light-Emitting Diode) devices was driven by a local dimming control core. The block-wise register approach substantially reduced the number of required line-buffers and shortened the latency time. The measurements made in the laboratory indicate that the backlight system reduces power dissipation by an average of 48 percents and exhibits no visible distortion compared relative to the fixed backlighting system. The system was successfully demonstrated in a 42-in. LCD TV, and the contrast ratio was greatly improved by a factor of 100.

Keywords

Backlight Local-dimming LCD LED Image 

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Copyright information

© Springer Nature Singapore Pte Ltd. 2019

Authors and Affiliations

  1. 1.National Yunlin University of Science and Technology/ElectronicDouliuTaiwan

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