Quiroga Mellado, Juan AntonioVargas Balbuena, JavierBelenguer Dávila, TomásServín Guirado, ManuelEstrada, Julio César2023-06-202023-06-202011-01-111094-408710.1364/OE.19.000638https://hdl.handle.net/20.500.14352/43957© 2011 Optical Society of AmericaA two-step self-tuning phase-shifting method is presented. The phase-step between the two interferograms is not known when the experiment is performed. Our demodulating method finds, in a robust way, this unknown phase-step. Once the phase-step is estimated we proceed to phase demodulate the interferograms. Moreover our method only requires the fringe patterns to have a constant unknown phase-shift between them. As a consequence, this technique can be used to demodulate open and closed-fringed patterns without phase-sign ambiguity. The method may be regarded as a self-tuning quadrature filter, which determines the phase-shift between the two fringe patterns and finally estimates the demodulated phase map. The proposed technique has been tested with simulated and real interferograms obtaining satisfactory results.engjournal articlehttp://dx.doi.org/10.1364/OE.19.000638http://www.opticsinfobase.org/open access535AlgorithmExtractionÓptica (Física)2209.19 Óptica Física