Open AccessSpatially separated heterodyne grating interferometer for eliminating periodic nonlinear errors
Author(s) -
Xu Xing,
Di Chang,
Pengcheng Hu,
Jiubin Tan
Publication year - 2017
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.25.031384
Subject(s) - optics , grating , astronomical interferometer , heterodyne (poetry) , interferometry , nonlinear system , heterodyne detection , physics , frequency domain , diffraction grating , spatial frequency , laser , computer science , acoustics , quantum mechanics , computer vision
Periodic nonlinear errors caused by frequency mixing are serious obstacles for increasing the resolution of heterodyne grating interferometers. To eliminate the periodic nonlinear errors, a spatially separated heterodyne grating interferometer is proposed in this study. Two modulated beams with different frequencies are transferred respectively by two fibers, which form a spatially separated construction. A couple of comparison experiments in both time domain and frequency domain are designed and conducted. The results of the frequency-spectrum analysis experiment showed that the periodic nonlinear errors were no larger than 0.086 nm, which proved that the proposed system was effectual in eliminating periodic nonlinear errors.