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arXiv · 1505.05036

A four-pole power-combiner design for far-infrared and submillimeter spectroscopy

Giuseppe Cataldo·Samuel H. Moseley·Edward J. Wollack
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Abstract

The far-infrared and submillimeter portions of the electromagnetic spectrum provide a unique view of the astrophysical processes present in the early universe. Micro-Spec ($μ$-Spec), a high-efficiency direct-detection spectrometer concept working in the 450-1000-$μ$m wavelength range, will enable a wide range of spaceflight missions that would otherwise be challenging due to the large size of current instruments and the required spectral resolution and sensitivity. This paper focuses on the $μ$-Spec two-dimensional multimode region, where the light of different wavelengths diffracts and converges onto a set of detectors. A two-step optimization process is used to generate geometrical configurations given specific requirements on spectrometer size, operating spectral range, and performance. The canonically employed focal-plane constraints for the power combiner were removed to probe the design space in its entirety. A new four-stigmatic-point optical design solution is identified and explored for use in far-infrared and submillimeter spectroscopy.

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Giuseppe Cataldo, Samuel H. Moseley, Edward J. Wollack. 2015-05-19. A four-pole power-combiner design for far-infrared and submillimeter spectroscopy. https://doi.org/10.1016/j.actaastro.2015.04.002

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