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Published on: December 3, 2013
Least-squares modal estimation of wrapped phases: application to phase unwrapping
1Departamento de Fisica Aplicada, Facultad de Fisicas, Area de Optica, Universidade d e Santiago de Compostela, E-15782, Galicia, Spain. fajap@usc.es
Abstract:
Phase unwrapping continues to be an important step in those techniques that obtain the phase from Fourier transforms. We propose a fast two-dimensional phase-unwrapping algorithm that has been specially designed to be used as part of an iterative algorithm. It can be used also as a final step of a phase retrieval process with other unwrapping techniques. The algorithm consists of a modal least-squares estimation of the wrapped phase by using as inputs to the linear estimation the derivative of the wrapped phase. A theoretical description of the method, simulations, and experimental validations are presented.
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