Whole-Field Optical Systems and Image Processing Techniques for Shape and Deformation Measurements
نویسنده
چکیده
The authors have been developing some novel methods to measure shape, deformation, stress and strain of structures using whole-field optical methods and image processing techniques. In this paper, these methods are introduced, and recent methods on sampling moiré method, whole-space tabulation method (WSTM), and windowed phase-shifting digital holographic interferometry (Windowed PSDHI) are detailed. Sampling moiré method can analyze phase-information of the moiré patterns obtained by changing the sampling phase of a recorded grating pattern and can provide accurate displacement distributions. WSTM can measure shape or displacement distributions accurately in real-time using tables without calculation. Windowed PSDHI can measure subnanometer displacement and analyze three-dimensional displacement distributions of structures. The theory, the optical systems and the applications are shown.
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