本論文主要目的在研究以液晶混合光聚合材料並施以全像曝光製作可調式液晶相位光柵，且論文中將針對液晶相位光柵之臨界電壓、繞射效率極值等光電特性進行討論。實驗中以氦氖雷射做為曝光光源，為了達到較高的光柵繞射效率，我們針對許多實驗條件如光聚合材料濃度、曝光劑量、混合材料加熱處理等進行研究。最後，以最佳的實驗條件將混合材料之液晶盒做為全像術之物光與參考光干涉之記錄元件，並可獲得影像還原。
實驗中的光聚合物有兩種，分別是RM257與NOA65。在RM257方面的結果，對混合材料加熱處理後，可以大幅縮短曝光時間與光強度達到光柵製作之目的。然而，我們也觀察到RM257混合材料的液晶盒有『不聚合現象』發生當曝光光強度大於0.4 mW/cm2時。但若再添加另一額外的NVP材料，則『不聚合現象』便消失，如此，較高的曝光強度(如曝光強度高於0.4 mW/cm2以上)時，全像曝光製程仍可正常使用。實驗結果證明利用1 mW/cm2曝光15秒條件可以製作出繞射效率約33%之相位光柵，此數值已非常接近Raman-Nath理論值33.9%。
在NOA65方面的結果，實驗發現NOA65濃度必須高於15 wt%以上才能製作出良好的光柵結構，藉由曝光強度、曝光時間，以及樣品溫度的控制等實驗條件，其最佳可達約16%之繞射效率。

In this thesis, the main investigation is to fabricate tunable liquid crystal phase gratings by means of holographic exposure of a He-Ne laser on liquid crystal cells filled with mixture of liquid crystals/polymer composites (LCPCs). The optical performance of fabricated phase gratings is also measured and investigated including operation threshold voltages, maximum diffraction efficiency, demonstration of holographic application, and so on.
Using two different types of photocurable monomers to fabricate liquid crystal phase gratings, we also compare their optical performance of phase gratings individually fabricated with RM257 and NOA65. We find that the mixing process of RM257 and liquid crystals at a fixed higher temperature (~65˚C) significantly reduce holographic exposure time for fabricating phase gratings. A strange and inscrutable phenomenon is observed that is no photo polymerization in photo exposed areas when using photo irradiance over 0.4 mW/cm2. However, this inscrutable phenomenon disappears when extra adding a little material of NVP in original mixture. At present, the 33% diffraction efficiency is available in this study, which is very close to the maximum value of 33.9% based on Raman-Nath theory.
By contrast, 16% diffraction efficiency of the phase grating with 15 wt% NOA65 is available.

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