本論文乃研究利用紫外光雷射雙光束干涉場引致產生具備有序二維網格微結構之膽固醇液晶聚合物模板全像光柵。實驗結果首先發現以單光束激發膽固醇液晶與單體混合物之聚合過程，會因高分子單體朝曝光面移動與聚合造成膽固醇液晶螺距收縮而產生縱向內應力，進一步引發Helfrich形變效應而導致無序二維網格微結構，此結構有沿著缺陷線排列之特性。實驗結果進一步發現，改以雙光束干涉場曝光可使得所產生之二維網格微結構變成有序排列，此乃因為一維光強度週期調制之干涉場在樣品近照光邊之光強處先行聚合出一排排有序缺陷線陣列，進一步引導因Helfrich形變效應所導致的二維網格微結構變得排列有序。此論文同時探討干涉光曝光條件(例如光強度、雙光束夾角等)與膽固醇液晶螺距大小等對所形成有序二維網格光柵之有序程度及繞射特性之影響。此外，此模板經過洗淨/回灌過程後仍展現高度可電壓調控繞射特性證明其穩定性與可外部調控性。此研究成功利用缺陷線來操控因Helfrich形變效應所導致的微結構具備有序性，進一步實現此著名現象於光電應用之潛力。

This thesis studied an ordered two-dimensional (2D) grid microstructure based on a cholesteric liquid crystal (CLC) polymer holographic grating template induced by a two-beam interference field. Experimental results first found that the preferential polymerization of the CLC-monomer mixture near the exposed side the sample will induce a longitudinal internal stress due to the shrinkage of the pitch of the CLC, further causing the Helfrich deformation effect to cause the disorder 2D grid microstructure. This structure has the characteristics of being arranged along the defect line. Experimental results further found that changing to two-beam interference field exposure can make the 2D grid microstructure generated in an orderly arrangement due to the guiding of the polymer defect-line array formed initially along the top-intensity linear regions of the interference field. This study also probed into the influences of interference light exposure conditions (such as light intensity, double-beam included angle, etc.) and the pitch of the CLC on the degree of order and diffraction characteristics of the ordered 2D grid grating. In addition, this template exhibits high voltage-regulated diffraction characteristics after the washing-out/refilling process to prove its stability and external controllability. This study successfully exploited defect lines to manipulate the microstructures caused by the Helfrich deformation effect to have orderliness, further realizing the potential of this famous phenomenon in optoelectronic applications.

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