結合旋轉分析板與波長位移術之偏光儀

A Polariscope Using Rotating Analyzer and Wavelength Shift Techniques

張家豪(Chia-Hao Chang)

指導教授 ： 林世聰

國立臺北科技大學/電資學院/光電工程系研究所/碩士(2007年)

https://doi.org/10.6841/NTUT.2007.00238

摘要

本論文用於量測雙折射光學波板之相位延遲量、快慢軸方向、光程差與波板階數，實驗架構包含三種不同波長之雷射光源、半圓偏光儀系統、旋轉分析板、光遮斷器與鎖相放大器所組成。本文利用光遮斷器調變參考光產生方波訊號，而旋轉分析板則調變量測光產生弦波訊號，兩訊號送入鎖相放大器，即可得到待測波板造成的相位延遲量。由於鎖相放大器所顯示的相位延遲量在-180°~180°範圍內，超出此範圍則會產生誤判，因此加入波長位移的技術，透過波長改變前後所產生的相位延遲量變化差值，可由此差值之正負號確定波板慢軸方向。透過波長改變與相位延遲量的變化，可計算出波板造成的光程差，進一步可判斷出波板的階數。本論文的量測系統具有操作簡便、快速量測與非破壞性檢測之優點，透過量測已知資訊的驗證波板可得到相符的結果，也證明本論文的可行性與正確性。

關鍵字

旋轉分析板 ； 波長位移 ； 偏光儀 ； 波板

並列摘要

This thesis arms to develop a measurement system for detecting phase retardation, slow axis orientation, and optical path difference of a waveplate. The structure of the system includes three laser light source, a half circular polariscope, a rotating analyzer, an optical chopper and a lock-in amplifier.
One of the lasers is first separated into a reference beam and a measurement beam. The reference beam passes through the chopper to generate a reference signal. The measurement beam travel through the half circular polariscope and rotating analyzer to generate a measurement signal. As these two signals are guided into the lock-in amplifier, the phase retardation of the waveplate can be obtained. And as the phases corresponding to the lasers are all detected, the slow axis orientation and the optical path difference of the waveplate can be determined.
An optical setup was constructed to realize the measurement system. Experimental results agree the validity and applicability of the measurement system.

並列關鍵字

rotating analyzer ； wavelength shift ； polariscope ； waveplate.

參考文獻

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