An analysis is presented of the intensity of ghostlines, caused by a periodic nonlinearity in the travel of the movable mirror in a two-beam Fourier spectrometer, used in the step-record mode. The ghostlines are studied for two cases: (1) for a modulus spectrum calculated after a complex Fourier transform; (2) for a spectrum calculated by a cosine Fourier transform after symmetrizing the measured interferogram. In the latter case, the intensity of the ghostlines is also dependent on the position of the center of the interferogram. This dependence has been examined theoretically and verified experimentally for the case of a monochromatic source. It is shown that an appropriate choice of the position of the center of the interferogram and the use of a cosine Fourier transform can reduce the intensity of the ghostlines drastically in practice.
© 1983 Optical Society of America
M. J. H. van de Steeg, H. W. H. M. Jongbloets, and P. Wyder, "Reducing the effects of ghostlines in a step-record Fourier spectrometer," Appl. Opt. 22, 862-866 (1983)