Open Access5-beam grating interferometry for extended phase gradient sensing
Author(s) -
Krzysztof Patorski,
Łukasz Służewski,
Maciej Trusiak
Publication year - 2018
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.26.026872
Subject(s) - optics , interferometry , fresnel zone , physics , diffraction , wavefront , fresnel diffraction , phase (matter) , amplitude , phase retrieval , demodulation , diffraction grating , grating , fourier transform , computer science , channel (broadcasting) , telecommunications , quantum mechanics
A novel, single-shot, low-cost, multidirectional lateral shear interferometer for extended range wave front phase gradient sensing has been developed. It exploits the Fresnel diffraction field, which is formed by the five lowest diffraction orders of a simple binary amplitude checker grating. The Fresnel intensity pattern encodes information on four directional partial derivatives of the wave front under test. It has been theoretically, numerically, and experimentally shown that for larger gradient phase objects or shear amounts only the diagonal derivative information is easily accessible. The horizontal and vertical direction gradient maps are strongly amplitude modulated. Therefore, their demodulation becomes a challenging task. The same feature has been found in widely used quadriwave interferometer, which was developed at ONERA, France. The results of analytical and numerical studies and experimental works, including fringe pattern processing and phase demodulation, are presented.