利用光配向製作多域分割垂直配向模式液晶顯示元件之研究

Photo-alignment for a Multi-Domain Vertically Aligned Mode Liquid Crystal Cell

張俊仁(Jun-Ren Chang)

指導教授 ： 陳殿榮 ； 吳俊傑

國立臺北科技大學/機電學院/光電工程系所/碩士(2005年)

摘要

多域分割垂直配向技術(multi-domain vertical alignment，MVA)擁有許多優點，如高對比、廣視角、無灰階反轉…等。現有MVA必須製作凸塊(bump)，以控制液晶排列的預傾方向，而有液晶分子不同步傾倒的缺點。
本研究使用垂直配向模式來探討高分子單體對液晶預傾角的影響。利用高分子穩定配向技術(polymer-stabilized alignment)製作VA液晶盒，並量測其光電特性。我們將高分子單體混入液晶中，並且對液晶盒照射UV光及外加電壓Vuv，製造一控制液晶分子配向之高分子網(polymer network)，使液晶分子預先有個傾倒的方向，以改善液晶響應時間。最後將找到的最佳參數(濃度比例、外加電壓)應用於MVA-LCD上。我們成功的(1)利用外加電壓控制預傾角 (2)加入高分子單體使液晶的配向變好 (3)找到最佳參數為1wt% Vuv=8.5V及0.5wt% Vuv=8.5V (4)改良MVA液晶盒使其具有更快的響應速度 (5)工廠只需加微量的高分子，而不需更改製程，即可改善面板特性。

關鍵字

liquid crystal ； polymer network ； polymer- stabilized alignment ； MVA

並列摘要

The technology of multi-domain vertical alignment owns many advantages like high contrast ratio and wide viewing angle. The present technology of multi-domain vertical alignment manufactures bumps to control the alignment of liquid crystal and has the shortcoming of asynchronous liquid crystal alignment.
In this thesis, an improved technology of multi-domain vertical alignment is presented. The technology of polymer-stabilized alignment is employed to manufacture the LC cell and then the optical and electrical characteristics of the LC cell are measured. We use the mixture of monomer and liquid crystal, illuminated with ultraviolet to form the polymer network which can control the alignment of liquid crystal molecules. In UV illumination process, a curing voltage Vuv is applied on the mixture to make the liquid crystal with pretilt angle. In summary we succeed in: (1) Controlling the pretilt angle of liquid crystal by applied voltage. (2) Making a better liquid crystal alignment by forming polymer network. (3) The optimum parameter 1wt% when Vuv=8.5 V and 0.5wt% when Vuv=8.5 V are obtained. (4) The improved LC cell of multi-domain vertical alignment can shorten the response time of liquid crystal. (5) The factories only need to mix little monomers to improve the characteristic of LC cell without changing the manufacturing processes.

並列關鍵字

liquid crystal ； polymer network ； polymer- stabilized alignment ； MVA

參考文獻

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