本論文採分子動力學方法模擬液晶在配向膜上配向情形，再用統一原子模型（united atom model）簡化液晶和聚亞醯胺（polyimide, PI）分子，統一原子模型的優點為減少龐大的計算量，節省運算時間，且兼顧模擬結果與現實的吻合。
液晶顯示器面版包括：玻璃基板、彩色濾光膜、偏光板及配向膜。其中配向膜的分子結構、溝槽形狀與液晶分子所產生的錨定作用，會影響未施加電場時配向膜上的液晶配向。故本文將探討聚亞醯胺分子所構成的配向膜與製作不同形狀的奈米溝槽（Ｖ形、方形）對於液晶配向的影響。
模擬結果顯示，液晶分子會平行於聚亞醯胺分子所構成的微溝槽，且溝槽的形狀會影響液晶之配向，而配向的優劣以有序參數代表，其中有序參數值為在Ｖ形槽的液晶有序參數大於方形槽的液晶有序參數。

In this study, we study on orientation of nematic liquid crystal at polyimide substrate by molecular dynamics simulation and use united atom model to simplify all hydrogen atoms of liquid crystal and polyimide. The advantage of united atom model greatly reduces computation times and increases computational efficiency which is in agreement with experiment.
The liquid crystal display contains glass substrate, color filter, polarizer, and alignment layer. The anchoring strength between the molecular structure of alignment layer and liquid crystal affects alignment of the liquid crystal on alignment layer when the electric field does not apply. This article discusses the effect of alignment layer composed of polyimide and the different shape of microgroove ( V- and square-shaped ) which influences the alignment of liquid crystal. The alignment of liquid crystal is represented by order parameter.
The result of this study shows that liquid crystal orients in a direction perpendicular to the polyimide main chain direction and the molecular orientation of liquid crystal is influenced by the shape of microgroove. For the V-shaped polyimide liquid crystal alignment layers, the order parameter of liquid crystal is higher compared with that from the square-shaped polyimide liquid crystal alignment layers.

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