【摘要】 菱形相位展开算法以菱形为路径进行相位展开,具有展开速度快、易理解等特点而倍受亲睐,但是当展开路径上遇到不可靠点时相位展开容易出错,并向后累计,形成拉线或孤岛现象。因此,本文提出一种改进的菱形相位展开算法,先用大津法对调制度进行二值化形成基本模版,并以该模版非零区域为导航找出截断相位分布中的极点,通过对极点的所在位置进行标记进而生成极点模板;再根据基本模版与极点模板将极点与不可靠点进行隔离,从而对可靠点进行相位展开;最后根据相位的连续性原则,利用相位逼近和插值拟合方法校正不可靠点处的相位,从而得到完整并且逼真的相位展开结果。实验结果验证所提算法的可行性和有效性,表明改进菱形相位展开算法可以有效地避免相位展开中的拉线和孤岛现象。更多还原

【Abstract】 As for phase unwrapping along a rhombus-shaped path,the rhombus phase unwrapping algorithm is very popular because it has the features of rapid expanding,easy understanding and so on.However,it is error prone and the error will accumulate to form lines or islands when unreliable points are encountered on the unwrapping path.Therefore,an improved rhombus phase unwrapping algorithm is proposed.First,a basic mask is made by binarization of the deformed pattern′s modulation based on Otsu and the poles are found on the wrapped phase in the corresponding area to the nonzero area of the basic mask,so a pole mask can be formed by locating the pole coordinates.Second,according to basic mask and pole mask,the pole and unreliable points in the wrapped phase can be isolated,then the reliable wrapped phase can be unwrapped efficiently.Finally,according to the principle of phase continuity,phase approximation and interpolation fitting are used to correct the phase at the unreliable point,so that complete and realistic phase unwrapping results can be obtained.The experimental results show the feasibility and validity of the proposed algorithm.It reveals that the improved rhombus phase unwrapping algorithm can effectively avoid the line-like and the island-like phase errors.更多还原