The Novel Design of Direct LED Backlight with Lens Caps and Parabolic Reflectors.pdf

© 2008 OSA / AOE 2008 a125_1.pdf SaK51.pdf SaK51.pdf The Novel Design of Direct LED Backlight with Lens Caps and Parabolic Reflectors * ** ** Kuang-Lung Huang Jin-Jia Chen Kai-Hung Cheng *Institute of Electrophysics, MingDao University,369 Wen-Hwa Rd., Peetow, ChangHua, 52345, Taiwan E-mail: khuang@.tw **Department of Electrical Engineering , National Changhua University of Education, 2, Shi-Da Road, Changhua City, Taiwan. E-mail: jjchen@.tw Abstract: A novel design of direct LED backlight is presented. The module is composed of white light LEDs, parabolic reflectors and novel lens caps. The predicted uniformity is up to 92%. c 2008 Optical Society of America OCIS codes: 220.2945 1. Introduction In recent years, the acknowledgement of the environment protection is getting higher and higher. Therefore, the CCFL light source, which has mercury inside, has been substituted by LED light source gradually. Using LED as a light source in the backlight design has a lot of benefits, as discussed in previous papers [1, 2]. But, if only using a high power LED source and without any further treatment, the design is difficult to reach high optical performance. In this paper, a novel design of direct LED backlight module will be presented. The module is divided into 40 sub-modules. Each