Generalized phase-shifting interferometry by parameter estimation with the least squares method

Autor: Rigoberto Juarez-Salazar, Cruz Meneses-Fabian, Carlos Robledo-Sanchez, L. M. Arévalo Aguilar, Fermin Guerrero-Sanchez
Rok vydání: 2013
Předmět:
Zdroj: Optics and Lasers in Engineering. 51:626-632
ISSN: 0143-8166
DOI: 10.1016/j.optlaseng.2012.12.020
Popis: A simple non-iterative algorithm for generalized phase-shifting interferometry is proposed. This algorithm recovers the wrapped phase from two or more interferograms with unknown phase steps between 0 and π rad. The proposal is based on the least squares method to calculate four parameters: background and modulation light, phase steps and wrapped phase distribution. This algorithm, by a new interferogram normalization procedure, can handle interferograms with variable spatiotemporal visibility overcoming the restriction and drawbacks from usual variable spatial visibility approaches. The algorithm works very well for processing interferograms which include many fringes. This behaviour will be explicated and discussed. The effectiveness and robustness of this algorithm are supported by numerical simulation and by the evaluation of experimental interferograms. The phase-shift estimation quality is verified by two different techniques. By the properties of this algorithm, such as the low computing time and free of user intervention, we believe it could be used in automatic real-time applications.
Databáze: OpenAIRE