In optical interferometry are several optimization methods applied to estimate the phase of a closed fringe pattern. There are several optimization techniques which play an important role in finding the phase interferogram parameters. In this work, a Genetic Algorithm in combination with Frequency guided Sequential Demodulation are implemented to estimation the phase of synthetic fringe pattern. The method gives good results in demodulation of closed fringe patterns. Results in processing time are similar to traditional optimization techniques, but the method presents computer simplifications to others algorithms.
The phase shifting algorithms are a widespread method in the technical and scientific literature for relatively noninvasive measurements of a variety physical variables. PSI (phase-shifting interferometry) techniques consist in acquiring at least three interferograms to obtain the wrapped phase. It is important to emphasize that if these acquired intensity images are inadequate, the measurement would have an error associated. The presence of miscalibration or mechanical vibrations in an interferogram can cause an inaccurate measurement; it is possible to design a phase shifting algorithm with a better performance. The present work proposes a novel methodology in order to determine the existence of a miscalibrated interferogram in a four steps phase shifting algorithm by applying the Radon transform.