本論文中使用共路徑電光調變外差干涉技術發展出一套多功能偏光干涉系統，用以測量光學非等向性材料之各項參數。此系統已成功應用於葡萄糖溶液之濃度量測、線性雙折射材料之二維全域量測、高靈敏扭轉向列型液晶厚度之單點及全場量測、扭轉向列型液晶之單點及全場多參數量測；並以不加外場之方式，成功測量向列型液晶與polyimide配向膜間之強方位角錨定能，本研究以單一架構搭配不同之訊號處理方式，實現了針對光學非等向性材料之多功能多參數單點及全場量測系統。
在線性雙折射材料之量測上，此系統達成主軸角度及相位延遲量之全場及全域量測，主軸角度及相位延遲量之全場量測標準差分別為0.14度及0.27度。此系統利用電光調變器取代旋轉偏振片的機械式調變方式，改良了強度比率法(total intensity ratio method)，達成快速扭轉向列型液晶盒之厚度單點量測，實驗驗證可於兩秒內得到液晶盒之厚度。在同一共路徑外差干涉架構下，使用CCD為光接受器，於一個調變週期內擷取三張積分影像，藉此求出外差干涉訊號之相位分佈，並達到全場量測扭轉向列型液晶層厚度之目的，此高靈敏相位影像偏光系統之扭轉向列型液晶層延遲量(retardation)量測解析度可達0.5 nm。論文中以外差干涉訊號的相位及強度比作為多目標基因演算法中的目標值，演算法將找出最適合的基因(即液晶參數)來對應到所要之目標值，此方法成功量測出扭轉向列型液晶盒的入射液晶導軸方位角、扭轉角以及液晶盒厚度；而以外差訊號之二維相位分佈作為目標值，更可同時求出液晶盒的入射液晶導軸方位角、扭轉角以及液晶盒厚度之二維分佈。論文中更進一步以楔型液晶盒為樣本，量測其扭轉角及厚度分布，進而求出液晶與polyimide之方位角錨定能，此方法毋須外加電場或磁場，待測樣本亦不需符合waveguiding regime之特殊條件。
藉由光學外差共路徑干涉的量測架構，可降低環境擾動對於訊號的影響，並改善訊噪比(signal-to-noise ratio)。實驗結果確認了此方法用於單點及全場量測線性雙折射材料及扭轉型液晶盒參數的可行性，光學外差式偏光架構對於相位量測具有高度靈敏性，而所得的各參數與設計值十分接近。本系統除了可快速的得到液晶盒厚度之分佈，可用於對於液晶線上製程檢測，亦可穩定的同時量測扭轉向列型液晶的方位角、扭轉角及液晶盒厚及方位角錨定能等參數，對於光學非等向性材料之特性分析提供有力之工具。

In optical measurement field, heterodyne interferometry technology is an important technique for precise measurements. In this research, a multi-function polariscope with heterodyne-based configuration is developed for the characterization of optical anisotropic materials such as the glucose concentration, the principal axis angle and phase retardation of linear birefringence material (LBM), and parameters of twisted nematic liquid crystal (TNLC) cells.
For 2-dimensional LBM measurement, the dynamic ranges of the principal axis and phase retardation measurements extend from 0° to 180° and 0° to 360°, respectively. The proposed system not only enables full-range measurements of the slow axis angle to be obtained, but also allows a decision to be made as to whether the principal axis labeled by the manufacturer is the slow axis or the fast axis. The standard deviations of slow axis angle and phase retardation measurements are found to be 0.14° and 0.27°, respectively. The proposed system replaced rotating polarizer with an electro-optic modulator (EOM) to modify total intensity ratio method (TIRM) and showed the capability of high-speed single-point TNLC cell gap measurement. The experimental results confirm that the proposed approaches yield comparable accuracy to the conventional methods, and sufficient intensity signals to determine the cell gap can be obtained in just 2 seconds. In the same optical configuration, a highly phase-sensitive imaging polariscope for the mapping of spatially-distributed cell gap of a TNLC is proposed. The dynamic range of retardation which is around 0.7 μm without ambiguity in the proposing method is also larger than that in the previous reports. By using standard 8-bit gray level charge coupled device (CCD), the experimental results show that the standard deviation of 1.8 nm in the 2-D measurement of cell thickness has been obtained. The retardation resolution of 0.5 nm of the proposed method is also achieved and is better than that of the Stokes parameters determination method with high gray level CCD (16-bit brightness resolution). Furthermore, the intensity ratios and the phases of the detected heterodyne signals are used for the inverse calculation in the LC cell parameters by applying a genetic algorithm (GA) approach. The experimental results show that the average deviation of 0.01 ° and 0.013 μm in the measurement of twist angle and cell thickness have been obtained. The average deviation of 0.23° in the measurement of entrance director angle has also been achieved. Based on phase-sensitive imaging polariscope, the 2-D experimental results show that the 2-D standard deviation of 0.4°, 0.7°, and 0.032 μm for determining the 2-D distributions of azimuth angle, twist angle, and cell thickness have been obtained. A TNLC wedged cell was therefore used as the sample for characterizing the anchoring property of LC and alignment layer. The measured variation curves between real twist and cell gap were used to determine the azimuthal anchoring strength and the anchoring strength of 160 μJ/m2 and 36μJ/m2 between rubbed polyimide (PI) and two different LC materials are obtained.

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