以往相位移法在數位剪像術的應用都是利用步進馬達、壓電致動器推動試件或參考面，或是轉動偏極板以得到不同相位移干涉條紋圖像，容易產生量測時間過長的問題。在本文中利用空間相移法(Spatial phase shifting)，使用極化分光鏡(Polarized Beam-Splitter, PBS)，偏極板(Polarizer)，四分之一波板(Quarter-Wave Plate, QWP)搭配直角菱鏡(Right Angel Prism)、分光鏡(Beam-Splitter)讓單一相機同時截取兩種相位，建立出單一CCD瞬間相位移數位剪像系統(digital shearography system)，可在變形前擷取不同相位移光斑圖，隨著時間瞬間擷取變形後光斑圖，利用四步相位移法得到全場相位值，再經由相位展開法(phase unwrapping)及相位值與應變轉換後，可得試件不同時間下的應變狀況。
模擬分析方面，利用高斯分佈函數給定一應變場，模擬出光斑圖，再經過四步相移計算可證實此演算法可得給定應變場。實驗光路部分經由AutoCad畫出光路圖，證實四張剪切光斑圖可得到相同的剪移量，並可直接的由CCD擷取。實驗的方面由雙相位單一CCD實驗架設擷取四張光斑圖，利用數位影像相關法(Digital Image Correlation, DIC)所得最佳參數校正四張光斑位置位移和旋轉量並求出全場相位。最後量測動態試件，量測試件為利用升溫量測壓克力動態變形的情形。
相位結果利用數位影像處理方法及各種演算法解決光斑雜訊太多等問題，結果並不是非常的理想，但經由探討後，本實驗架構是可行的，但有幾點困難是必須再克服的。

Usually, phase shift method is applied to digital shearography, which is using stepping motors, piezoelectric to move reference mirror or rotate the polarizer to get different interference fringe image. It takes a long time for measuring. In this paper, single camera can capture speckle images with different phase simultaneously by using the method of spatial phase shifting, which is using polarized beam-splitter (PBS), polarizer, quarter-wave plate (QWP), right angle prism, beam-splitter. It could set up a single-CCD instantaneous phase-shifting digital shearography system, which can capture speckle images with different phase before deformation, and capture speckle images after time-dependent deformation. By applying phase shifting and phase unwrapping method, the strain in test specimen at different time can be determined.
In the simulation and analysis part, we use Guassian distribution function to construct strain field, and simulate speckle image for four difference phase. After four-step phase shifting is calculated, the result confirms the algorithm can obtainable in the given strain field. Then, we draw light path by AutoCad, four of speckle image can get the same shearing distance, and can capture by CCD directly.
In experiment part, four speckle images are captured by two-bucket single camera setup, the position and rotation of these images can be corrected by the digital image correlation method and the full field phase can be determined. At last, the paper measure for dynamics test, we obtain the dynamic deformation of PMMA by rising temperature.
This research uses digital image process and different algorithm to solve the problem of speckle noise. The experiment result is not very ideal. However, further discussed, the experimental structure is feasible. There are the problems must be overcome.

Keywords: Spatial phase shifting、Instantaneous phase-shifting、Digital shearography、phase unwrapping、Digital image correlation、dynamic measurement

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