Direct LED backlight for large area LCD TVs: Brightness analysis

Ching Cherng Sun, Ivan Moreno, Shih Hsun Chung, Wei Ting Chien, Chih To Hsieh, Tsung Hsun Yang

Research output: Chapter in Book/Report/Conference proceedingConference contributionpeer-review

13 Scopus citations

Abstract

A direct or bottom LED backlight is a key concept in large area LCD displays because it does not use a light guide, is flat, and is easy to assemble. In this paper, a method of luminance management for a bottom LED backlight is proposed and demonstrated. We analytically calculate both the power consumption and brightness uniformity in function of: screen brightness, screen size, backlight thickness, transmittance of the LCD panel, reflective cavity efficiency, gain and cone angle of enhancement films, LED array configuration, and the average luminous flux and radiation pattern of a single LED. Moreover, a 42-inch LCD television with this backlight design approach is made and demonstrated. The bottom backlight incorporates an array of RGGB 4-in-1 multi-chip LEDs within a highly reflective box behind a diffuser and a dual brightness enhancement film. We predict with an accuracy of 94% the brightness uniformity and with 96% the luminance level.

Original languageEnglish
Title of host publicationSeventh International Conference on Solid State Lighting
DOIs
StatePublished - 2007
Event7th International Conference on Solid State Lighting - San Diego, CA, United States
Duration: 27 Aug 200729 Aug 2007

Publication series

NameProceedings of SPIE - The International Society for Optical Engineering
Volume6669
ISSN (Print)0277-786X

Conference

Conference7th International Conference on Solid State Lighting
Country/TerritoryUnited States
CitySan Diego, CA
Period27/08/0729/08/07

Keywords

  • Backlight
  • LCD television
  • LEDs
  • Luminance

Fingerprint

Dive into the research topics of 'Direct LED backlight for large area LCD TVs: Brightness analysis'. Together they form a unique fingerprint.

Cite this