电子散斑干涉载频调制形貌测量方法的分析

Analysis of the shape measurement by carrier modulation in electronic speckle pattern interferometry

根据电子散斑干涉载频调制测量物体形貌的基本原理,物体表面的微小偏转可引入包含物体高度信息的载波干涉条纹。将物体的偏转视为变形,对物体变形与载波干涉条纹之间的关系进行了讨论,得出了离面位移引入载波和面内位移引入含有物体高度信息相位的结论。发现利用典型电子散斑干涉系统测量物体形貌效果最好,并通过实验得到了验证。

Based on the basic principle of the shape measurement by carrier modulation in electronic speckle pattern interferometry （ESPI） , a carrier pattern containing altitude information is formed on the object surface when the test object is tilted a small angle. The points on the surface of the object are displaced a distance when the test object is rotated. The phase difference introduced by the deformation and the phase difference introduced by the deflection of the object were compared. It is found that the carrier is introduced by the out-plane displacement and the phase containing altitude information is contributed by the in-plane displacement., Several ESPI methods for shape measurement by using carrier modulation are discussed. The typical ESPI system is effective in shape measurement because the carrier pattern containing altitude information is distinct and the phase of the object can be derived by Fourier transform easily.