本論文主要目的為圓孔型液晶透鏡性能之研究。圓孔型液晶透鏡液乃是利用圓孔型電極在液晶層中產生非均勻對稱性電場，使得液晶分子方向分佈形成適當之折射係數梯度條件，當入射光進入液晶透鏡後，由於不同位置的光程差而達到匯聚或發散光的能力。此類型的液晶透鏡由於非均勻對稱性電場形式，常常與液晶配向方式互相影響，當電壓驅動時，容易出現液晶分子轉向的不連續性，一般稱為不連續線(disclination line)。
為了改善驅動電壓時所產生的不連續線，我們發現適當的操作電壓的方法可以去除不連續線的出現。另外，我們改變上基板玻璃厚度使得液晶層中之電場比較接近垂直電場，以減少不連續線出現的機會，雖然實驗結果證明可行，但是，增加上基板玻璃厚度會降低液晶透鏡的聚焦效能。

In this thesis, we mainly study optical performances of the circular hole-pattern electrically driven liquid crystal lenses. The circular hole-pattern electrode provides a symmetric non-uniform electrical field, which drives the director orientation of spatial liquid crystals in order that suitable distribution of gradient refractive indices can be achieved in the cells. When an incident light beam passes through the cell, light beam can be converged or divergent according to the conditions of optical path difference generated by refractive index distribution. The phenomena of disclination lines are usually observed for this kind of lenses because of conflicts of affecting liquid crystal orientaion between electrical field and alignment force.
In order to avoid disclination lines, we found that applying voltage with a suitable way or increasing the thickness of upper glass layer was very useful. But, increasing thickness of upper glass layer is not a good way because optical capabilities of lenses decrease.

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