A unique spectrometer system, the Multi-Mode Spectrometer (MMS), has been developed. The MMS integrates a scanning Michelson interferometer, a flat-field grating, and a linear photodiode array detector into a single spectrometer system. With these components, the MMS is capable of applying dispersive, interferometric, or combined dispersive/interferometric techniques for enhanced spectrometric flexibility. The effects of source fluctuation and redistributed photon noise can be reduced. In addition, the MMS has unique capabilities in data compression, application of internal standards, and noise spectrum analysis. / Ph. D.