垂直配向液晶盒在不同電極結構下的光學特性探討

Study on the electro-optical characteristics of vertical aligned nematic liquid crystal cells with various electrode structures

曾柏皓(Bo-Hau Tseng)

指導教授 ： 吳俊傑

共同指導教授 ： 陳殿榮

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2014年)

摘要

液晶顯示器的驅動方式有很多種，例如扭轉向列型(twist nematic, TN)、垂直配向(vertically aligned, VA)、水平電場(in-plane switching, IPS)、邊緣電場(fringe field switching, FFS)等驅動模式，其中以垂直配向驅動方式最為廣泛應用。垂直配向具有高對比度，但為了要呈現更高品質的影像，垂直配向有幾個缺點需要改善，例如窄視角、較長的響應時間…等。
本篇利用模擬軟體LCDMaster3D研究不同電極結構對於垂直配向液晶盒光學特性的影響。因為不同電極結構會造成電場分佈改變，因而使液晶分子排列不同，所以我們在下基板透明電極(indium-tin oxide, ITO)設計三種不同形狀的電極結構，使液晶分子呈現螺旋狀及輻射狀排列得到較好的視角特性，並且在液晶材料中加入不同濃度的手性材料，觀察手性材料對光電特性的影響。

關鍵字

扭轉向列型 ； 垂直配向 ； 視角 ； 響應時間 ； 手性材料

並列摘要

Liquid crystal display has a lot of drive modes, such as twisted nematic, vertical alignment, in-plane switching and fringe field switching drive mode, etc. The vertical alignment mode display has been widely used. It has high contrast and low driving voltage, but in order to render a higher quality image, there are several drawbacks need to be improved, such as view angle, response time, etc.
In this study, we have simulated the optical properties of various electrode structures for the vertical alignment mode by using simulation software, LCDMaster3D. Due to electrode structure variation will cause changes in the electric field distribution, thus a different arrangement of the liquid crystal molecules, so we designed three kinds of transparent electrode structures in the bottom substrate. Each electrode makes the liquid crystal molecules in omnidirectional alignment to achieve a wide view angle. We also mixed various concentrations of the chiral material in the liquid crystal to observe the effect of chiral materials on optical characteristics.

並列關鍵字

twisted nematic ； vertical alignment ； view angle ； response time ； chiral

參考文獻

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