Two-Dimensional LED Tandem Backlight Module for Large Scale Scanning LCD

• Main Authors: Yuan-Jung Yao, 姚源榕
• Other Authors: 田仲豪
• Format: Others
• Language: en_US
• Published: 2007
• Online Access: http://ndltd.ncl.edu.tw/handle/89530645016184727553

碩士 === 國立交通大學 === 電機學院光電顯示科技產業專班 === 96 === The aim of this thesis is to utilize tandem wedge shaped light guides to accomplish the large scale scanning field-sequential-color liquid crystal display. The field-sequential-color system has a lot of advantages such as high efficiency, high color gamut. However, due to the response time of the liquid crystal is insufficient fast, the duty cycle of the light source is restricted. This situation leads to luminance reduction especially in large size application. In order to overcome this issue, the scanning field-sequential-color backlight system is proposed. In this system, the color state is sequentially scanned from up to down during a whole frame. Nevertheless, if the conventional light guide is used to perform the scanning field-sequential-color backlight module, two different color states will appear on the screen simultaneously. The light penetration will occur inside the light guide, and that will lead the image color distortion. For this reason, each scanning partition of the field-sequential-color scanning backlight application should be an isolated segment to avoid the color mixing error. Based on this purpose, the tandem wedge shaped light guides are assembled to realize large scale application. Through the experiment, the uniformity by 9 points of LG was 84% associated with the brightness enhance film and diffuser. The FHWM (Full Width at Half Maximum) of the extraction light is �b30 degree in scanning direction. The leakage from the illuminated block to the adjacent stripes is only 9.8%.