Please use this identifier to cite or link to this item: http://hdl.handle.net/11455/2656
標題: 結合統計分析之相位展開技術研究
作者: 許文鴻
關鍵字: 相位展開技術;Phase Unwrapping;電子斑點干涉術;ESPI
出版社: 機械工程學系
摘要: 
光學量測技術為高精密且非破壞性檢測,而其最大的問題在於條紋解析度,條紋解析度差就會影響到影像後處理的精確度,所以本文針對相位展開技術的應用與探討作研究,進行改良與效能的比較。
相位展開技術通常分為兩個部分,一是先運用合適的濾波器,把相位圖中的雜訊濾除掉,之後即可利用較簡單的相位展開技術重建相位,另一部份則是直接對相位重建,故對於雜訊的忍受度要更高,也就是我們所謂的雜訊免疫的相位展開技術,本篇論文也針對這兩部分提出不同的見解與處理方法。
首先針對前濾波器的特性及性能進行探討,進而改善傳統方法的缺點,使此法能將高雜訊的相位圖中的雜訊濾除,而不影響到原始相位的準確度。另外,本文提出另一區域型技術,針對phase jump的特性,分區編碼出transition zone和global zone,進而找出這些區域的相對高度,完成相位重建。

Phase unwrapping is a necessary step for phase retrievals. The unwrapping works could be intuitively divided into two categories. One is to unwrap phase maps directly by noise-immune algorithm, and the other is to apply a suitable filter to reduce the number of phase inconsistencies of the wrapped map so as to simplify the following unwrapping implementations.
Local histogram is adopted in this study to eliminate phase inconsistencies of noisy wrapped map. Computational Simulation and experimental verification show that the filtered result is better than that achieved in other ways. Contrarily, a global and local hybrid algorithm is developed to by pass the inconsistency-related problems of a noisy wrapped map to yield its true phase field directly.
URI: http://hdl.handle.net/11455/2656
Appears in Collections:機械工程學系所

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