在光學檢測及干涉光學的領域中，對干涉條紋還原其相位分佈是必要的程序。然而，在使用雷射光作為光源時，將會產生光斑雜訊、進而影響相位還原的精確度。
本論文以二維經驗模態分解法消除雷射光斑，並比較使用不同內插法之二維經驗模態分解法，在消除雷射光斑的結果上有何差異。最後，透過資料庫的建立，我們除了使二維經驗模態分解法在消除雷射光斑的工作上成為自動化工具，也觀察到其在雷射光斑的消除結果上會與條紋週期、條紋明晰度以及雷射光斑的SNR有很高的關聯性。

Phase-extraction from fringe patterns is an inevitable procedure in the field of optical metrology and interferometry. However, speckle noise will introduce and influence the precision of wrapped phase map when a coherent light is used.
In this thesis, we use the bidimensional empirical mode decomposition (BEMD) to perform the speckle-reduction. Moreover, different interpolation method in BEMD will be used to compare their performance in speckle-reduction. Finally, the database will be developed to make the BEMD a robotic tool to reduce noises. And the database also points out that the performance of BEMD is highly related to the fringe period, the fringe visibility, and the SNR of speckle noise.

Chapter 1 緒論．．．．．．．．．．．．．．．．．．．．．．．．．． 1
Chapter 2 EMD 與BEMD．．．．．．．．．．．．．．．．．．．．．． 4
2-1 EMD 簡介．．．．．．．．．．．．．．．．．．．．．．． 5
2-2 EMD 演算法．．．．．．．．．．．．．．．．．．．．．．． 10
2-3 BEMD．．．．．．．．．．．．．．．．．．．．．．．．． 13
Chapter 3 利用BEMD 消除干涉條紋的雷射光斑．．．．．．．．．．．． 18
3-1 雷射光斑的特性．．．．．．．．．．．．．．．．．．．．． 19
3-2 利用電腦模擬干涉條紋圖案．．．．．．．．．．．．．．． 24
3-3 電腦模擬與實驗結果比較．．．．．．．．．．．．．．．．． 27
3-3.1 實驗架設．．．．．．．．．．．．．．．．．．．．． 27
3-3.2 結果比較．．．．．．．．．．．．．．．．．．．．． 30
3-4 BEMD 消除結果與討論．．．．．．．．．．．．．．．．． 33
3-4.1 Standard deviation．．．．．．．．．．．．．．．．． 33
3-4.2 運算時間比較．．．．．．．．．．．．．．．．．．． 33
3-4.3 消除結果比較．．．．．．．．．．．．．．．．．．． 34
3-4.4 總結．．．．．．．．．．．．．．．．．．．．．．． 41
Chapter 4 資料庫的建立與討論．．．．．．．．．．．．．．．．．．． 42
4-1 IMF 移除數目資料庫．．．．．．．．．．．．．．．．．． 43
4-2 光斑移除百分比資料庫．．．．．．．．．．．．．．．．． 46
4-3 牛頓環的雷射光斑消除．．．．．．．．．．．．．．．．． 49
Chapter 5 結論與未來工作．．．．．．．．．．．．．．．．．．．．．．59
參考文獻 ．．．．．．．．．．．．．．．．．．．．．．．．．．．． 61

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