الفهرس 
Fourier Transform Optical SpectrometersOnly 14 pages are availabe for public view
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Abstract
This research presents a general analysis for the wedge interferometer used in the Fourier Transform Spectrometer. The wedge interferometer is superior over conventional Michelson interferometer in immunity against mechanical vibration of the moving mirror. It also reduces sampling errors. This is done by using two wedges one stationary and one moving. The optical path difference results from the lateral motion of the moving wedge. In this work we study the effect of miniaturizing both interferometers and discuss the advantages and disadvantages of the wedge spectrometer when compared to conventional Michelson Spectrometer. Diffraction effects in both spectrometers are studied by considering a Gaussian beam and calculating the visibility degradation against different parameters of the interferometer. We found that the wedge interferometer performs better than the Michelson interferometer. Further, the dispersion effects in the wedge due to variation of the refractive index of the wedge material studied. We study the dispersion effect using approximate equation. Then, we propose a rigorous algorithm to cancel the dispersion the dispersion effect. Finally, the degradation of signal-to-noise ratio due to different source is considered. We presented the effect of error sampling due to error in moving arm. We discuss the error in linear motion of the mirror in Michelson and the linear lateral motion of the wedge. We also discuss the error of misalignment of the wedge due to rotation of the moving wedge about the center of the base of this wedge. Finally, the temperature effects on the refractive index of the material of the wedge and the theram expansion of the wedge are analyzed. We found that the wedge is superior for error in linear motion. For small motion error the Michelson interferometer is superior due to temperature effects. The rotation specifically of order milliradian, the wedge gives bad results and bad signal-to-noise-ratio.