平面快速切換模式之二維梳狀電極結構的參數設計模擬與光學特性分析

Analyzer of optical properties and design parameters of two-dimensional comb-like eletrode structures for IPS mode

劉晏綺(Yen-Chi Liu)

指導教授 ： 黃振球

元智大學/工程學院/化學工程與材料科學學系/碩士(2005年)

摘要

本研究係利用日本shitech公司的光學設計模擬軟體針對IPS mode作梳狀電極結構的設計及光學特性的模擬，共分為五大部分包括摩擦配向角度、電極線寬及電極間距、預傾角、液晶層厚度及電場大小…等等參數的改變，透過光學計算分析，將得到的結果包含液晶元件中液晶分子的軸向分布和電位分布以及液晶顯示器的光學特性等，再進一步討論找出最佳化參數；另外根據模擬結果，提出三個解決方法，第一，液晶材料的改變，含氟化合物的液晶材料之誘電異方性高可增加電壓保持率且低雙折射率的物理性質可改善色偏移的問題，第二，外加二軸性延遲片的光學補償作用下，降低傾斜方向漏光的問題，並提高對比度及超廣視角的光學特性，最後是將畫素/共通電極設計為鋸齒彎曲電極，來改善色偏的問題，以求得更佳的顯示品質達到廣視角之要求，進而在實際應用上有所幫助。

關鍵字

誘電異方性 ； 折射率 ； 延遲片

並列摘要

In this study, the optical properties of the comb-like electrode on In-Plane-Switching mode liquid crystal displays were analysed using LCD Master software from Japanese Shintech. Five principle parameters, including rubbing angle, applied voltage, cell gap, pretilt angle, comb-like electrode width and distance between two electrodes were used to simulate with optical analyzer. The result of director alignment distribution and equal-potential distribution were discussed in the liquid crystal cell. We also tried to find best parameters. According to the results, we propose three solutions to improve the performance of the present technology. First, a fluorinated liquid crystal compound was suggested to increase voltage-holding ratio owing to its small birefringence, which can improve color shift in the display image. Second, biaxial retardation films were applied to reduce light leakage. Finally, we suggested a zigzag electrode pattern to reduce color shift in the displays. We expect to obtain a IPS mode LCD with high quality and wide viewing angle characteristics using the simulated result.

並列關鍵字

design ； IPS

參考文獻

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