Bianchetti Arturo, Veiras Francisco E, Etchepareborda Pablo, Vadnjal Ana Laura, Federico Alejandro, Kaufmann Guillermo H
Appl Opt. 2015 Mar 10;54(8):2132-40. doi: 10.1364/AO.54.002132.
This paper presents a method for amplitude and phase retrieval in simultaneous π/2 phase-shifting heterodyne interferometry. The used optical setup admits the introduction of a temporal carrier and simultaneously verifies the two-beam interferometry equation for each intensity signal, which are π/2 rad out of phase (quadrature). The spatiotemporal recovering process is obtained by isolating the object amplitude and phase using wavelet transform analysis of the temporal series composed by the difference between the measured pixel intensities corresponding to each quadrature signal. This process is subsequently improved by introducing a framework based on the synchrosqueezing transform, which recovers the data of interest with higher accuracy when very low scattering amplitudes and phase excursions must be determined in noisy working conditions. The advantages and limitations of the presented method are analyzed and discussed using numerical simulations and also experimental data obtained from temporal speckle pattern interferometry.
本文提出了一种用于同时π/2相移外差干涉测量中幅度和相位恢复的方法。所使用的光学装置允许引入时间载波，并同时验证每个强度信号的双光束干涉测量方程，这些信号的相位相差π/2 弧度（正交）。通过对由对应于每个正交信号的测量像素强度之差组成的时间序列进行小波变换分析，来分离物体的幅度和相位，从而获得时空恢复过程。随后，通过引入基于同步挤压变换的框架对该过程进行改进，当在噪声工作条件下必须确定非常低的散射幅度和相位偏移时，该框架能以更高的精度恢复感兴趣的数据。使用数值模拟以及从时间散斑图案干涉测量获得的实验数据，对所提出方法的优点和局限性进行了分析和讨论。
