Design of the Backlight Module Elements

• Main Authors: Shin-Hua Chu, 朱信樺
• Other Authors: Chao-Hsien Chen
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/57496336327117453701

碩士 === 國立高雄應用科技大學 === 機械與精密工程研究所 === 99 === This study aims to investigate the two major parts in backlight units: light guide plates and diffuser film. In order to make this experiment work systematically and efficiently, it uses Excel VBA program to call out the optical software Lighttools, set parameters and ray tracing, and collect data to Excel tables for further analysis. Some researches neglected the interactive effects between factors in backlight units such as light guide plates and diffuser films. Taguchi methods are used to analyze the main effects of and interaction between the light guide plate dots structure permutation factors. The experimental result shows that the effect of interaction of the two factors has 60% influences in this system, which is essential for determining the optimal combination of the factors. Therefore, those two factors with strong interactions are chosen for further full-factorial experiments; the uniformity increases 8% after the first experiment and 16% after the second experiment, respectively. The direct backlight module trends to be smaller in the market. Because of the necessity of the finite thickness to approach light uniformity, it is generally hard to design thin backlight module with effective light uniformity. In order to decrease the thickness of direct backlight module, this study analyzes the performance of different types of diffusion films in the second part. Three kinds of microstructures, pyramid, hemisphere and circular cone, are compared with a general diffusion film. The effects of various thickness of the backlight module are also considered. The experimental results show that the efficiency and light diffusion of those films with microstructures are twice better than the general diffusion film. Moreover, there is no obvious difference among those three films with microstructures such that we can choose the one which is easiest to be manufactured or cheap in a practical task.