Ordones Sotero, Servin Manuel, Padilla Moises, Choque Ivan, Muñoz Antonio, Flores Jorge L
Appl Opt. 2020 Jul 10;59(20):6224-6230. doi: 10.1364/AO.393153.
In this paper, we introduce an iterative scheme for phase demodulation of interferograms with nonuniformly spaced phase shifts. Our proposal consists of two stages: first, the phase map is obtained through a least squares fitting; second, the phase steps are retrieved using a statistical robust estimator. In particular, we use Tukey's biweighted M-estimator because it can cope with both noisy data and outliers in comparison with the ordinary least squares estimator. Furthermore, we provide the frequency description of the algorithm and the phase demodulation allowing us to analyze the procedure and estimation according to the frequency transfer function (FTF) formalism for phase-shifting algorithms. Results show that our method can accurately retrieve the phase map and phase shifts, and it converges by the 10th iteration.
在本文中，我们介绍了一种用于具有非均匀间隔相移的干涉图相位解调的迭代方案。我们的方案包括两个阶段：首先，通过最小二乘拟合获得相位图；其次，使用统计稳健估计器检索相位步长。具体而言，我们使用了Tukey的双加权M估计器，因为与普通最小二乘估计器相比，它可以同时处理噪声数据和异常值。此外，我们提供了算法的频率描述和相位解调，使我们能够根据相移算法的频率传递函数（FTF）形式来分析该过程和估计。结果表明，我们的方法能够准确地检索相位图和相移，并且在第10次迭代时收敛。
