Abstract
A relatively new type of spectrometer based on the Spatial Heterodyne Spectroscopy (SHS) concept recently joined the list of successfully flown satellite instruments. SHS is related to the Michelson interferometer and thus the Fourier Transform spectrometer, but it has no moving parts and it measures the interferogram in the spatial domain rather than the time domain. SHS instruments have been built for the far and near ultraviolet, the visible, near and thermal infrared. This article reviews a recent patent that is covering an approach to assemble an SHS interferometer using compression forces and precision spacers which allows a robust and economical design, self-aligned assembly, and the option to replace optical components relatively easily. As an example, we show a thermal infrared SHS interferometer that was designed using this approach.
Keywords: Spectroscopy, spatial heterodyne spectroscopy, remote sensing, interferometry, infrared, SHIMMER instrument, SHIMCAD interferometer, beamsplitter, space flight instrumentation, monolithic fabrication
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