Processing of Interferogram Symmetrization in Optical Fiber Fourier Spectrometer
LI Bao-sheng1,LIU Yong2,WANG An2
1. School of Instrument Science and Opt-electric Engineering, Hefei University of Technology, Hefei 230009, China 2. Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China
Abstract：The asymmetry of an interferogram is caused by off-center sampling or defects in the fiber interferometer, and the spectra from Fourier cosine transformations of one-sided interferogram have phase errors. A method was firstly applied to symmetrizing interferogram by using the convolution technique in optical fiber Fourier spectrometer (FFTS). The phase error can be derived from the central portion of the interferogram. Symmetrization function was obtained from the Fourier transform of the phase error. Thus in spatial domain the symmetrization function convolved with original interferogram, and the spectra with correction of phase errors resulted from the symmetrized interferogram. Experimental study shows that the method efficiently corrects the phase error in FFTS. The method not only overcomes the disadvantages of two-sided interferogram, but also has better accuracy of the results.
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