穆勒矩陣影像偏光儀

Abstract

這個研究可以大幅延伸了閃頻式偏光儀的應用。首先，多取一個量測點可以不須校正閃頻式偏光儀對光彈調變器的初始相位。相較於傳統的旋轉元件偏光儀，不僅減少了元件的旋轉次數而提升量測速度，也降低了因旋轉元件而造成的光束偏移。由於對閃頻式偏光儀所做的分析，我們可以進行系統的最佳化，並從理論上驗證了閃頻式偏光儀的精準度。 結合一四分之一相位延遲片，我們將原本僅量測史托克向量的偏光儀延伸至可以量測 16 個穆勒矩陣的參數。因此可以量測各式樣品的偏光特性，並使得此二維影像系統得以量測各種材料，包含非等向性材料。在本文中，也透過空氣、石英以及散射介質來驗證此系統的精準度。利用人為植入的小球以增加介質的濁度，在透過穆勒矩陣的極分解，我們可以證明本技術將可大大的降低生物組織散射效應的影響。利用優化理論，我們可以證明此穆勒矩陣量測技術是使用最佳搭配的偏振態以及解析態。

This work is an extended application of stroboscopic illumination polarimetry. At first, we added an extra temporal phase to de-associate the initial phase from photoelastic modulator, which can reduce the calibration procedure. This technique not only reduces the time consuming in the rotating elements polarimetry, the beam deviation caused by rotation can also be diminished. An algorithm has been provided to theoretically verify the accuracy and precision of this stroboscopic illumination polarimetry. Furthermore, we added a quarter waveplate in the photoelastic modulated polarimetry to extend the Stokes vector polarimetry to a 2D Mueller matrix measurement. We also optimized the polarization state generator (PSG) and the polarization state analyzer (PSA) in this polarimetric system. In comparing the figure of merit of PSG and PSA with that of other configurations of polarimetry, we found that this stroboscopic illumination Mueller matrix polarimetry is a very competitive polarimetric technique. By almost half mechanical rotations as it is needed in the conventional system, we performed the Mueller matrix measurement in measuring the optical activity of a quartz crystal with a quartz Cornu pseudodepolarizer. By polar decomposition technique in latex particles contained medium, we also verify that the birefringence can be restored in the scattering medium.