| The very high spectral resolution is the most outstanding feature to the time-modulated Fourier transform imaging spectroscopy (TMFTIS). Any other existing type of spectroscopy does not have this feature. Together with the high accuracy advantage, TMFTIS is currently well accepted and much used at scientific and industrial laboratories for various kinds of applications, and its application at atmospheric remote sensing and the measurement of the hyperfine spectrum has become an inevitable trend.The biggest problem associated with the use of a Michelson interferometer as a Fourier transform spectrometer is the tilt of the moving plane mirror during scanning. It is extremely difficult to solve the basic problem mechanically, so we have to searchfor optical solutions.In order to develop the very-high-spectral-resolution Fourier transform imaging spectrometer, this dissertation systematically and in depth studied the key theoretical and technical problems of the TMFTIS, and made some achievements of innovation in scientific research.In this dissertation the tilt tolerance of the moving plane mirror in Michelson interferometer is systematically analyzed by means of modulation depth and phase error. The lateral shift of the single moving cat's-eye retro-reflector and the tilt of its secondary mirror are analyzed. Some novel types of interferometers, the moving-mirror-pair interferometer, the moving-double-sided-mirror interferometer, the novel moving-cat's-eye-pair interferometer and the novel moving-corner-cube-pair interferometer, are presented for the first time. Their principle and properties are studied. The novel moving-corner-cube-pair and the novel moving-cat's-eye-pair nterferometer have neither tilt nor shearing problems, and the OPD value is eight times the displacement of the moving element. So the larger maximum OPD value can be created by the straight reciprocating motion of the moving element. Therefore, the very high spectral resolution can be obtained by the novel moving-corner-cube-pair interferometer or the novel moving-cat's-eye-pair interferometer. In addition, the novel moving-cat's-eye-pair interferometer is very applicable to very-high-resolution Fourier transform spectrometers for any wave-number region from the far infrared down to the visible if the cat's-eye retro-reflector comprises a parabolic primary and a spherical secondary. The novel moving-corner-cube-pair interferometer is almost ideal for the very-high-resolution Fourier transform infrared spectrometers.In this dissertation the moving-optical-wedge interferometer and a modified moving-optical-wedge interferometer are presented, and their principle and properties are studied. The ratio of the OPD value and the displacement of the moving optical wedge may be very small (for example, 0.3), if the values of the refractive index and the wedge angle of the optical wedges are chosen properly. Thus, the moving-optical-wedge interferometer is not so sensitive to the velocity variation of the moving element compared with the Michelson interferometer. That is, the moving-optical-wedge interferometer can reduce the impact of the velocity varation on the interferogram sampling error.In this dissertation the two-output moving-corner-cube-pair interferometer and the two-output moving-cat's-eye-pair interferometer are presented, and their principle and properties are studied. Each one generates two output beams received by two detectors. The resulting interferogram is made up of the difference between the signals of the two detectors, and these signals have the same amplitude and opposite phases. Hence, these two novel two-output interferometers remove the most important intensity distortions from Fourier transform spectra recorded with nonlinear detectors, and they have neither tilt nor shearing problems. The OPD value is four times the displacement of the moving element, so the instrumental resolution of the above novel two-output interferometers is higher than the Michelson interferometer.
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