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Predicting phase steps in phase-shifting interferometry in the presence of noise and harmonics
Rajesh Langoju1, Abhijit Patil, Pramod Rastogi
1Applied Computing and Mechanics Laboratory, Ecole Polytechnique Fédérale de Lausanne, 1015 Lausanne, Switzerland.
Abstract:
A novel method for estimating pixelwise phase step values in phase-shifting interferometry is presented. The method is based on the linear prediction property of the intensity fringes recorded temporally at a pixel on the charged-coupled device. The salient features of the method lie in their ability to handle linear miscalibration errors, to compensate for the presence of harmonics in an optical configuration and detector nonlinearity, and to allow for the use of arbitrary phase steps. The robustness of the proposed method is studied in the presence of noise and a comparison with several benchmarking algorithms is performed. The simulation results show the efficiency of the algorithm in retrieving the wrapped phase.
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