改进的菱形解相位法在相位展开中的应用

The Application of Improved Rhombus Phase Unwrapping Algorithm in Phase Unwrapping

为解决菱形解相位法在展开复杂相位场时容易出现拉线或孤岛的问题,提出了菱形解相位法的改进算法。该算法首先结合Goldstein枝切法找出包裹相位分布中的残差点,并将包裹相位图分为残差点区域和非残差点区域,然后对非残差点区域采用传统菱形解相位法进行展开,最后依据相位的连续性原则,利用最小二乘法拟合残差点区域的相位,获取实际相位的最佳逼近值,从而获得真实且可靠的相位展开结果。仿真结果表明:改进后的菱形解相位法可以有效展开复杂相位场,使拉线与孤岛现象减少了约70%。

In order to solve the problem that the rhombus phase unwrapping method easily form lines or islands when the measurement surface is too complex,this paper proposes an improved algorithm based on the rhombus phase unwrapping algorithm.First,the improved algorithm finds the residual points in the unwrapping phase by combining the Goldstein’s branch cut algorithm,and the wrapped phase map is divided into residual area and non-residual area.Then,the rhombus phase unwrapping algorithm is used to unwrap the non-residual area phase.Finally,according to the principle of phase continuity,the least square method is used to fit the phase of the residual area to obtain the best approximation of the actual phase,thereby obtaining authentic and reliable phase unwrapping results.The simulation results show that the improved algorithm can unwrap the complex phase field effectively,and the phenomenon of lines and islands is reduced by about 70%.