臺灣博碩士論文加值系統

近年發展的新型複合式導光板是在導光板上下表面建構稜鏡微
結構，即V-cut 導光板。V-cut 導光板雖然能有效利用光源能量，但
是其均勻度上的表現卻不如傳統網點式導光板。本文研究目的即在於
有效改善V-Cut 導光板均勻度不佳之情形。首先，在導光板下表面中
設計三種微結構，並分析對影響光通量最大之微結構形狀與幾何參
數。在導光板上表面中，設計有擴散膜散射特性之微透鏡，改善背光
模組均勻度。透過此散射微透鏡設計，能達到擴散膜的效果，因此可
以省去擴散膜的使用，節省成本。最後，本研究以7 吋背光模組模擬
分析，得到之導光板與擴散結構整合式設計，均勻度可達到90.6%。

Recently, the novel development of light guide is V-cut light guide
which integrate the micro-prisms on the top and bottom surface of the
light guide. Although the V-cut light guide can use the energy of light
source efficiently, its uniformity is lower than the traditional scattering
dots light guide. Therefore, the purpose of this study is to improve the
low uniformity phenomenon of V-cut light guide. First, this study designs
three micro-structures on the bottom surface of light guide, and analyzes
the influences of shape and geometric parameters of each micro-structure
on the luminous flux enhancement. Then, on the top surface of light guide,
the micro-lens are modeled which includes the scattering characteristic of
diffuser in order to improve the backlight uniformity. It can achieve the
effect of diffuser does through the design of scattering micro-lens, so it
can save the cost of diffuser. Finally, the integrated design of 7 inches
light guide and diffusion structures was simulated by using commercial
software LightTools, and the result shows that the backlight uniformity
can achieve 90.6%.

Contents

Contents i
List of Tables iii
List of Figures iv
摘要 vii
Abstract viii
Nomenclature ix
Chapter1 Introduction 1
1.1 Foreword 1
1.2 Components of Backlight 2
1.3 Literatures Review 6
1.3.1 Integrated Light Guides 6
1.3.2 Dot Pattern Designs 7
1.3.3 Refinements of Reflector 8
1.3.4 Material Components of Diffuser 9
1.4 Research Objectives 9
1.5 Content Frame 10
Chapter2 Fundamental Theories 17
2.1 LightTools Software 17
2.2 Reflection 19
2.3 Refration 20
2.4 Photometry Units 21
Chapter3 Research Method 26
3.1 Verification of Backlight Module 26
3.2 Design of Backlight Dimensions 26
3.3 Selection of Micro-structures 27
3.4 Prism Sheet with Rounded Vertices 31
3.5 Definition of Backlight Uuiformity 31
Chapter4 Results and Discussions 41
4.1 The Design of Bottom Surface of the Light Guide 41
4.2 The Design of Top Surface of the Light Guide 43
4.3 The Covers of Different Micro-structures 45
4.4 The Improvement of Backlight Uniformity 47
4.5 Comparisons of Three Integrated Designs 50
4.6 Revision of Prism Sheet 51
Chapter5 Conclusions and Future Prospect 71
5.1 Conclusions 71
5.2 Future Prospect 72
References 74

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