新型邊緣場效與橫向電場電極結構之低操作電壓和高光效率藍相液晶顯示器

Low Voltage and High Light Efficiency Transflective Blue-Phase Liquid Crystal Displays with New Electrode Designs based on Fringe In-Plane Switching Electrodes

呂柏叡(Po-Jui Lu)

指導教授 ： 蔡永傑

共同指導教授 ： 黃定洧(DIng-Wei Huang)

國立臺灣大學/電機資訊學院/光電工程學研究所/碩士(2021年)

https://doi.org/10.6342/NTU202102067

摘要

隨著科技進步，電子產品已成為人們生活中重要的一部分，大部分人們工作時都需要盯著螢幕看，對顯示器的需求是日益增加，顯示器中以液晶螢幕為主流，其中藍相液晶為下個世代相當熱門的研究題目，藍相技術的其中一個優勢在於不需要使用配相層，可以減少製作上的成本，以及亞毫秒的響應時間，能夠解決影像殘影，大幅地增加了顯示器的解析度與發光效率。但是目前藍相液晶顯示器需要克服高操作電壓及低穿透率的問題，若能改善此問題，藍相液晶是非常具有發展空間的。
本論文提出以半穿半反顯示器及Fringe in-plane switching(FIS)electrodes結構為研究主軸，希望能設計出光電曲線重合度高及操作電壓低的半穿透半反射式顯示器。根據本論文結構設計，藉由了解藍相液晶的物理特性，改變參數影響後，提供液晶盒大量的水平電場來降低操作電壓，並藉由反射區位置來改善原本電極上方的無效區問題。本論文將半穿透半反射顯示器按照穿透區及反射區來分別討論研究，並透過調整最佳參數，來達到低操作電壓、高穿透率和反射率、高重合度的光電曲線。

關鍵字

藍相液晶 ； 半穿半反式 ； Techwiz ； FIS模式

並列摘要

With the advancement of science and technology, electronic products have become an important part of people’s lives. Most people need to look at the screen while working, and hence the demand for displays is ever increasing. One of the potential next-generation displays is blue-phase liquid crystal display which has been actively researched and developed in recent years. The main advantages of blue phase technology include: i) no need of alignment layer which can reduce production costs, and ii) fast sub-millisecond gray-to-gray response time which can help solve motion-blur and help increase the resolution and light efficiency of the display by using e.g. field sequential technique. However, at the moment blue-phase liquid crystal display needs to overcome the problems of e.g. high operating voltage and low transmittance. If these problem can be solved properly, blue phase liquid crystal technology has a lot of potential for future displays with mass production.

In this thesis, we propose three new transflective blue-phase displays with the use of the concept of Fringe In-plane Switching (FIS) electrodes, hoping to produce transflective blue-phase displays with highly matched electro-optic curves and low operating voltage. In each of the design in this thesis, by understanding the physical properties of blue phase liquid crystals and influence of different parameters, we can change and optimize different parameters such that a large amount of horizontal electric field is produced to reduce the operating voltage of the liquid crystal cell. The position of the reflective area is also modelled to improve the ineffective area above the electrode. In this thesis, new designs for transflective blue-phase displays are studied and discussed for both transmission areas and the reflection areas. The optimal parameters are adjusted to achieve best-matched electro-optic curves with low operating voltage, high transmittance, high reflectance and high electro-optic curve matching.

並列關鍵字

Blue phase liquid crystal(BPLC) ； Transflective ； Techwiz ； Fringe In-plane Switching(FIS) electrodes

參考文獻

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