本論文主要目的在探討如何設計一外貼於電子紙上之增亮膜結構來 增加電子紙的亮度(反射率)。所使用之電子紙架構為微杯電泳式電子 紙，我們先針對電子紙表面特性與原始增亮膜設計進行光學與結構量測 分析，了解其表面反射特性與增亮膜特性，而後使用光學模擬軟體作最 佳化結構模擬設計，並實際製作出最佳化設計參數的增亮膜樣品來進行 驗證比較。 此研究結果顯示我們可以用比原設計更容易製作之結構來增加電子 紙亮度且亮度增益較不受入射光方向之影響，其亮度增益可達1.3 倍。我 們也使用增亮膜不對稱結構、二維結構與微透鏡結構等進行模擬分析； 不對稱結構可讓入射光於特定角度範圍入射情況下具增亮效果，亮度增 益約1.1 倍，也發現二維結構在特定光源入射角內具亮度增益且不受入射 光方向影響。本研究設計出最佳之電子紙增亮膜結構角度並分析出結構 對入射光與電子紙表面反射光之影響，也讓我們可以針對所使用之環境 光入射角度進行結構最佳化之增亮設計。而此研究結果未來亦可用於彩 色化電子紙或其他電子紙顯示器上以增加顯示器亮度 On the design of integrating luminance enhancement films into electronic paper (e-paper) display for higher brightness (reflectivity). Electrophoretic display (EPD) was selected as the e-paper technology for study. We started out by studying the surface property of e-paper and original enhancement film. Measurement and analysis on the optical and structural properties of the film were conducted in order to fully understand the optical enhancement and its impact to the surface reflectivity. Computational simulation was then carried out to optimize the structural design of the film. In the end, the optimal design was used to build the actual enhancement film for verification of the proposed solution. Based on this study, we achieved the goal of e-paper brightness enhancement with structure design that is less complicated to fabricate. The brightness enhance from this work is less prone to the impact of light incident angle and the enhancement is up to 130% of original design. Further simulation work was carried out for to explore the enhancement of asymmetric structure, two-dimensional structure and micro-lenses structures: asymmetric structure was predicted to achieve 110% luminance when incident light is angled within certain range. Also, two-dimensional structure could achieve enhancement at certain incident angle regardless the direction of the light. To summarize this work: we optimized the structural design of e-paper enhancement film and identified the impact of film structure to e-paper surface reflectance at different light incident angles. This work also provided the base for further structural optimization of enhancement film in order to adapt to the environment with different light incident angle. The observation and learning from this work can be further leveraged to colorful e-paper or other e-paper technology for the purpose of display brightness enhancement as the direction of future work.
