多重六角形電極結構應用於藍相液晶顯示器之研究

Multiple Hexagonal Electrode Design for Blue Phase Liquid Crystal Display

廖宜慶(Yi-Ching Liao)

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(2022年)

https://doi.org/10.6342/NTU202203667

摘要

隨著現今顯示技術的發展，液晶顯示器也必須在更進一步的提升效能，而藍相液晶是其中一個最有淺力的材料之一，此材料具有比一般液晶顯示器更佳的反應時間，並且可以利用現有的顯示器技術使其發光效率及解析度達到提升，然而經過不斷的試驗，此材料的穿透率較低以及有較高的穿透電壓，所以我們嘗試設計新的電極結構來提升穿透率及降低操作電壓。
本實驗室有提出過中空六角形結構，並且嘗試優化此結構。在本篇論文中，我們嘗試調整現有的結構，找到更佳的結構達到我們的目標。本篇論文主要有四個部分，第一部分調整中空六角形結構的不同參數，分析其中的優缺點並且找出此結構的最佳解，還有針對降低電壓而修改結構，第二部分對原本的結構增加一重電極使其變成二重中空六角形結構，比較改善後的電極優缺點，再對此結構調整不同參數並討論與穿透率及操作電壓的關係進而找到最佳化的電極結構，第三部分增加更多的電極變成多重中空六角形結構，比較結構間穿透率及操作電壓的變化，並利用第二部分得出的結構對八重中空六角形結構做最佳化得到最佳穿透率為92%其操作電壓為6.3V，第四部分，利用雙層結構來補償原有結構電極穿透無效區，嘗試在pixel及common上方增加電壓使其變成光亮區，而我們找到最佳化結構其最佳穿透率87%其操作電壓為7.1V。

關鍵字

藍相液晶 ； Techwiz ； 多重中空六角形電極 ； 雙層中空六角形電極

並列摘要

With the rapid development of display technology nowadays, liquid crystal display technology needs to further improve its performance. 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, there are at least two problems in blue phase liquid crystal: low transmittance and high operating voltage. So we need to design new electrode structures to decrease voltage and increase transmittance.
In our laboratory, we have previously proposed hollow hexagonal electrode and optimized this design. In this thesis, we will modify this structure further to achieve the goals. This thesis is mainly divided into four parts. In the first part, we changed various parameters of hollow hexagonal electrode structure, and analyzed their advantages and disadvantages to find the optimized value. Then we modified the structure to make voltage lower. In the second part, we added an electrode to the original structure to become a double hollow hexagonal electrode design, and compared their pros and cons. Then, we adjusted various parameters of this structure, and got the optimized values of transmittance and operating voltage. In the third part, we added more electrode rings into the original structure. We compared the changes about the transmittance and operating voltage, and we used the results from the second part to optimize the octuple hollow hexagon structure. We found the best transmittance of 92% and operating voltage of 6.3V. In the fourth part, we used double layers electrode to improve dead zone of the original structure. We added the electrode above the original pixel and common electrodes to make dead zone become bright zone. We found that the optimized structure has transmittance of 87% and operating voltage of 7.1V.

並列關鍵字

Blue-phase liquid crystal ； Techwiz ； multiple hollow hexagonal electrode ； double layers hollow hexagonal electrode

參考文獻

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