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Abstract We developed an interferometric system capable of generate four interferograms simultaneously with independent phase shifts employing modulation by polarization. The proposed system consists of three coupled interferometers: A polarized Mach–Zehnder interferometer (PMZI) which generates a primary pattern with crossed polarizations, coupled to two Michelson systems that serve as replicators of the primary pattern. In the proposed system, coupled three interferometers which generate four interference patterns with π /2 phase shifts. The four interference patterns can be detected simultaneously carrying a controllable phase shift by placing a linear polarizer in each replica obtained. To show the novelty and usage of the developed system on phase varying information temporal stability is presented and experimental results for static and dynamic variations. Highlights • Simultaneous phase shifting interferometry. • Experimental analysis of dynamic fast processes. • Coupled interferometers. [ABSTRACT FROM AUTHOR]

We report an optical implementation of a parallel phase-shifting quasi-common path interferometer using two modified Michelson interferometers to generate two interferograms. By using a displaceable polarizer’s array, placed on the image plane, we can obtain four phase-shifted interferograms in two captures. The system operates as a quasi-common path interferometer generating four beams, which are to interfere with alignment procedures on the mirrors of the Michelson configurations. The optical phase data are retrieved using the well-known four-step algorithms. To present the capabilities of the system, experimental results obtained from transparent structures are presented. [ABSTRACT FROM AUTHOR]

Abstract: In this paper, we propose a quasi common-path interferometer based on a two beams configuration (TBC) using simultaneous phase shifting interferometry modulated by polarization that shows insensitivity against external vibration. Due to the fact that the configuration is capable of obtaining two beams whose separation can be varied, according to the characteristics of the grid used, to obtain the interference patterns. It can be used to implement a quasi-common path interferometer that allows the measurement of dynamic events with high accuracy. For demodulate the fringe patterns generated by the optical system we using the conventional four step phase shifting method. Experimental results are also given. [Copyright &y& Elsevier]

Abstract: We report the evaluation of the topography of an object with projected fringes generated with a lateral cyclic shear interferometer (CSI) and we then compare the topography recovery obtained with the proposed method with the one obtained from a coordinate measuring machine (CMM). We also study how the fringes visibility along the z axis affects the retrieval. Finally, we discuss the advantages and drawbacks of this profilometry system. [Copyright &y& Elsevier]

In this study, we present an alternative method to measure the optical phase of transparent objects using two coupled interferometers. The first system comprises a polarized Mach–Zehnder interferometer (PMZI) that generates an interference pattern with crossed circular polarization. The second component is a compact rectangular Sagnac system (CRSS), which functions as a replicator and generates two interferograms. Because the trajectories of the two replicas are cyclical and collinear in the CRSS, no aberrations are produced; moreover, a controllable lateral displacement is achieved to separate the two replicas. By placing a mask with two linear polarizers at the output of the coupled system, a controllable phase shift is produced on each replicated interferogram. The results achieved with static transparent objects and a time-varying test are shown, demonstrating the feasibility of our proposed method. • A dynamic interferometric system is described. • Results of optical phase recovery from two simultaneous interferograms are presented. [ABSTRACT FROM AUTHOR]

• A low-cost simultaneous-phase-shifting system is implemented to analyze phase samples. • The optical components were recovered from recycled electronic devices. • Results of optical phase recovery from 2, 4, 7 and 9 interferograms are presented. • An Interferometric system for measurement the dynamic phase profile is described. • The dynamic method presented can be applied to several interferometric systems. In this research, we present the results obtained with a simultaneous phase-shifting interferometric system. This system is implemented with recovered optical components from recycled electronic devices from computer's DVD readers, LCD displays and commercial projectors. Such devices are beam splitters, diffraction gratings, mirrors, lenses and linear polarizers. These components were characterized by measuring their characteristics like transmittance, reflectivity and period of the gratings employed in order to verify its potential usage in dynamic interferometric measurements systems. The implementation is based on a Polarized Michelson interferometer (PMI) coupled with a 4- f system with a 2D diffraction grating. The system is capable of generate up to nine interferograms with comparable intensities and independent phase shifts that are modulated by polarization. We report the usage of four, seven, nine and two interferograms captured simultaneously and the processing of the interferograms is done by using conventional methods for extraction of the optical phase for each case, with the four-step algorithm for four steps, the symmetric algorithm of (N + 1) phase steps for 7 and 9, when using two interferograms the relative optical phase is calculated by means of the Vargas-Quiroga method. We analyze the temporal stability of the system by capturing 40 frames and showing its variation in each pixel to prove the repeatability of the proposed system. Related experimental results obtained for static and dynamic transparent samples are presented. [ABSTRACT FROM AUTHOR]