Computational tool for phase-shift calculation in an interference pattern by fringe displacements based on a skeletonized image

Abstract

In this manuscript an algorithm based on a graphic user interface (GUI) designed in MATLAB for an automatic phase-shifting estimation between two digitalized interferograms is presented. The proposed algorithm finds the midpoint locus of the dark and bright interference fringes in two skeletonized fringe patterns and relates their displacements with the corresponding phase-shift. In order to demonstrate the usefulness of the proposed GUI, its application to simulated and experimental interference patterns will be shown. The viability of this GUI makes it a helpful and easy-to-use computational tool for educational or research purposes in optical phenomena for undergraduate or graduate studies in the field of physics.

2D Relative Phase Reconstruction in Plasma Diagnostics

“…FTM is well-known for 2D phase reconstruction in optical metrology of surface flatness [31], surface height, strain [32] and defect [33] profilometry, surface motion [34], and 3D shape measurement. However, the spatial-carrier fringe behavior has also been used to observe extreme physical phenomenon [35] such as magnetic fields, electron waves and ultra-violet lithography, as well as beam propagation [36], plasma property measurement [37], refractive index studies of polymeric substrates [38], nano-scale surface metrology [39], corneal topography [40] and biological tissue characterization [41].…”

How do phase-shifting algorithms work?

“…In the laboratory experiments, the fringe-patterns are usually evaluated by simple techniques such as fringe counting [16]. For this, students receive the explanation that two adjacent fringes indicate a difference of the optical path equal to the wavelength of the employed laser source.…”