三維電極結構之設計應用在藍相液晶顯示器研究

3D electrode designs for Blue Phase Liquid Crystal Display

陳逸軒(Yi-Hsuan Chen)

指導教授 ： 蔡永傑

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2020年)

https://doi.org/10.6342/NTU202000448

摘要

隨著科技的發展，液晶顯示器成為生活中相當重要的電子產品。在這當中藍相液晶被視為具有潛力的材料之一，此材料有亞毫秒等級的反應時間，並能夠透過廠色序式液晶顯示器技術提升液晶顯示器的發光效率及解析度。不過藍相液晶顯示器主要的問題在於其低穿透率和高操作電壓，於是將透過設計新的電極結構來改善這些問題。本實驗室先前提出過新的電極結構，像是骨型電極結構及三維六角形電極結構。在本篇論文中，我們透過調整不同的參數、改變不同的形狀及排列來更進一步的研究這兩種電極結構。本論文主要分成兩個部分，第一部份我們藉由降低骨型電極結構的長度來改善穿透率表現，並且設計出錯位型六角形電極結構與骨型結構作比較來改善穿透率表現。第二部分我們藉由使用不同形狀的電極、不同的排列、不同的電極大小來改善三維六角形電極結構，並分析其優缺點。我們利用其六角形電極結構的概念去設計出八角型電極結構，並使用不同的定義分析他們在穿透率表現和操作電壓上的特點，因此得出影響穿透率的幾個重要因素。第一個因素為電極面積的大小，第二個因素為電場分佈方式，第三個因素為電極之間的間距。最後透過中空電極結構驗證蜂窩狀排列能比棋盤格狀排列有更好的穿透率表現。

關鍵字

藍相液晶 ； 六角形 ； 八角形 ； 中空 ； 骨型

並列摘要

By the development of technology, liquid crystal display has become a very important electronic product in our life. Blue-phase liquid crystal is considered to be one of the materials with such potential. Blue Phase liquid crystal material has sub-millisecond response time. Use of the blue phase liquid crystal can have the potential to improve light efficiency and resolution of the liquid crystal display by employing field-sequential-color (FSC) technique. However, the major problems of blue-phase liquid crystal display include high operating voltage and low transmittance. To improve these problems, we need to design new electrode structures. New electrode structures such as bone-shape electrode and 3D hexagonal electrode structures have been previously proposed by our lab. In this thesis, we further study and investigate these structures by e.g. using different parameters, shapes, arrangements, etc. This thesis is divided into two parts. In the first part, we attempt to improve the bone-shape electrode structure by decreasing the length of the bone-shape structure. We also design new dislocated hexagon electrode structures with improved transmittance compared to bone-shape structures. In the second part, we attempt to improve the 3D hexagonal structure design by using different types of electrode shapes, arrangements and sizes and analyzed their advantages and disadvantages. In this part, we also used the concept of the hexagon electrode to design octagonal electrode structures and used different definitions to observe and analyze their effects on transmittance and operating voltage. As a result, the major factors which could affect the transmittance were determined. The first factor is the area of the electrodes. The second factor is the electric field distribution. The third factor is the gap between electrodes. Finally, through the hollow electrode structures we have shown that the honeycomb (hexagonal) arrangement can have potential to perform better than the checkerboard (square-type) arrangement.

並列關鍵字

blue phase ； hexagon ； octagon ； hollow ； bone-shape

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