Phase-stepping algorithms for synchronous demodulation of nonlinear phase-shifted fringes
| Autor: | Manuel Servin, Ivan Choque, Sotero Ordones, Moises Padilla |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Signal Processing (eess.SP)
Physics business.industry Absolute phase Astrophysics::Instrumentation and Methods for Astrophysics Phase (waves) FOS: Physical sciences Atomic and Molecular Physics and Optics symbols.namesake Nonlinear system Interferometry Fourier transform Optics Pulse compression FOS: Electrical engineering electronic engineering information engineering symbols Demodulation Electrical Engineering and Systems Science - Signal Processing Wideband business Algorithm Optics (physics.optics) Physics - Optics |
| Zdroj: | Optics express. 27(4) |
| ISSN: | 1094-4087 |
| Popis: | Standard phase-stepping algorithms (PSAs) estimate the measuring phase of linear carrier temporal-fringes with respect to a linear-reference. Linear-carrier fringes are normally obtained using feedback, closed-loop, optical phase-shifting devices. On the other hand, open-loop, phase-shifting devices, usually give fringe patterns with nonlinear phase-shifts. The Fourier spectrum of linear-carrier fringes is composed by Dirac deltas only. In contrast, nonlinear phase-shifted fringes are wideband, spread-spectrum signals. It is well known that using linear-phase reference PSA to demodulate nonlinear phase-shifted fringes, one obtains an spurious-piston. The problem with this spurious-piston, is that it may wrongly be taken as a real optical thickness. Here we mathematically find the origin of this spurious-piston and design nonlinear phase-stepping PSAs to cope with open-loop, nonlinear phase-shifted interferometric fringes. We give a general theory to tailor nonlinear phase-stepping PSAs to demodulate nonlinear phase-shifted wideband fringes. 10 pages, 11 figures |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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