本論文主要目的為透過翻模複製法製作菲涅耳波帶片(Fresnel zone plate，FZP)，並將其與液晶材料結合後以電壓控制達成相位型菲涅耳液晶透鏡。實驗中針對不同厚度之菲涅耳液晶透鏡的繞射效率、偏振特性，以及成像效果等光學特性進行研究。
由於向列型E7液晶的短軸折射率與固化的NOA65光學膠折射率差異極小(~0.0023)，入射光進入奇、偶區時幾乎感受不到兩區間之折射率變化，因此可藉此光學特性與外加電場控制液晶分子轉態，達到菲涅耳液晶透鏡ON/OFF切換之目的。
菲涅耳液晶透鏡使用的液晶配向有水平配向(Homogeneous alignment，HA)和90度扭轉配向(90° twisted nematic alignment，TN)兩種類型。HA菲涅耳液晶透鏡為偏振相關元件，其焦點處光強度與入射光偏振方向相關；而TN菲涅耳液晶透鏡則為偏振無關元件。
由於NOA65二階結構是立體建立於玻璃基板上，奇、偶區液晶層厚度不同會造成相位分佈不均，使入射光因為感受到相位差而產生繞射，讓光線匯聚；當施加一電壓於液晶盒時，奇區因具有NOA65層結構導致液晶層感受到的電壓較偶區液晶層為小，故其液晶分子轉動程度亦較小，如此，奇、偶區對入射光便產生明顯的相位差及繞射現象。
根據理論，相位型二階菲涅耳透鏡的繞射效率為40.5%；而本研究結果在無間隙子與12μm厚度間隙子的HA菲涅耳液晶透鏡最大繞射效率分別為37.4%及37.15%，12μm、18μm及24μm的TN菲涅耳液晶透鏡最大繞射效率分別為23.76%、28.94%及35.28%。

In this thesis, the main investigation is to fabricate electrically switchable phase Fresnel liquid crystal lens (FLCL) by means of molding duplication. The optical performance of the fabricated phase FLCL is mainly measured and investigated including maximum diffraction efficiency, correlation of polarization, and imaging result.
The experiment interprets a phase FLCL that which is based on preformed polymer relief structure but uses two different kinds of aligned liquid crystal film, homogeneous alignment (HA) and twisted nematic alignment (TN) individually.
Experimental results the phase FLCL with homogeneous alignment has polarization dependent feature, polarization insensitive for 12μm and 18μm cell gap experiment sample with TN alignment, and polarization independent for 24μm cell gap FLCL lens with TN alignment.
At present, the high diffraction efficiency is available in this study, 37.15% and 35.28% for HA and TN phase FLCL individually, which is very close to the theoretical maximum value 40.5%.
Due to high diffraction efficiency and the refractive index of cured NOA65 (Norland Optical Adhesive 65) is matching to ordinary axis refractive index of nematic liquid crystal E7, the phase FLCL could successfully have not only the same focusing function with traditional convex glass lens, but also could be ON/OFF switch by additional electric field.

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