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A conical-diffraction-based cross-dispersed spatial heterodyne spectrometer (CDCDSHS) is presented. Conical diffraction is introduced, and one grating in the SHS is rolled around the central normal of its surface to expand the spectral range. The two-dimensional fringes are generated by the longitudinal-dispersion grating and the lateral-dispersion gratings through conical diffraction. Mathematical expressions are given for the parameter of an interferogram with varying spectral features and for the intensity distribution. Two examples are numerically simulated to demonstrate the performance of the spectrometer. The simulations show that the designed spectrometer can limit the interferogram of each spectral feature to be recorded by certain given rows of pixels on the charge-coupled device to avoid multiplexing disadvantages, and it can obtain clear features in each detailed spectrum with a higher signal-to-noise ratio than the conventional SHS while eliminating the need for filters or moving parts. Replacing the lateral-dispersion grating in the designed spectrometer with a mosaic grating can increase the spectral resolution and broaden the detectable spectral range. The designed spectrometer is also compact, very stable, and high-throughput. All mentioned advantages make the CDCDSHS a good prospect in broadband, high-resolution, high-sensitivity spectral measurement.

A modular cryogenic cross-disperser MOBIUS for the Large Binocular Telescope (LBT) is being developed to produce a simultaneous zJHK spectrum with a single LUCI, the LBT Utility Cameras in the Infrared. Its compact and exchangeable optical design fit within the existing focal plane mask frame of the LUCI spectrograph without any other hardware modifications. This unique deployable system enables a rapid acquisition of data over a wide wavelength range to better understand the unknown objects in the universe. [ABSTRACT FROM AUTHOR]

This paper presents a cross-dispersion prism-grating device using a plane transmission grating attached directly to a prism, which is different from traditional cross-dispersion grating-prism systems that are based on the reflection grating. Unlike conventional direct-vision grism or constant-dispersion grism in which both the prism and grating have the same dispersion direction, for this device the dispersion directions of the prism and grating are different. The analytical expressions for the cross-dispersion of this device are derived in detail and the formulas of the footprint of the dispersed spectra are given. The numerical results and ray-tracing simulations by ZEMAX are shown. The device provides a compact, small-sized and broadband cross-dispersion device used for the medium resolution spectrometer. [ABSTRACT FROM AUTHOR]

The Atmospheric Chemistry Suite (ACS) package is an element of the Russian contribution to the ESA-Roscosmos ExoMars 2016 Trace Gas Orbiter (TGO) mission. ACS consists of three separate infrared spectrometers, sharing common mechanical, electrical, and thermal interfaces. This ensemble of spectrometers has been designed and developed in response to the Trace Gas Orbiter mission objectives that specifically address the requirement of high sensitivity instruments to enable the unambiguous detection of trace gases of potential geophysical or biological interest. For this reason, ACS embarks a set of instruments achieving simultaneously very high accuracy (ppt level), very high resolving power (>10,000) and large spectral coverage (0.7 to 17 μm—the visible to thermal infrared range). The near-infrared (NIR) channel is a versatile spectrometer covering the 0.7–1.6 μm spectral range with a resolving power of ∼20,000. NIR employs the combination of an echelle grating with an AOTF (Acousto-Optical Tunable Filter) as diffraction order selector. This channel will be mainly operated in solar occultation and nadir, and can also perform limb observations. The scientific goals of NIR are the measurements of water vapor, aerosols, and dayside or night side airglows. The mid-infrared (MIR) channel is a cross-dispersion echelle instrument dedicated to solar occultation measurements in the 2.2–4.4 μm range. MIR achieves a resolving power of >50,000. It has been designed to accomplish the most sensitive measurements ever of the trace gases present in the Martian atmosphere. The thermal-infrared channel (TIRVIM) is a 2-inch double pendulum Fourier-transform spectrometer encompassing the spectral range of 1.7–17 μm with apodized resolution varying from 0.2 to 1.3 cm−1. TIRVIM is primarily dedicated to profiling temperature from the surface up to ∼60 km and to monitor aerosol abundance in nadir. TIRVIM also has a limb and solar occultation capability. The technical concept of the instrument, its accommodation on the spacecraft, the optical designs as well as some of the calibrations, and the expected performances for its three channels are described. [ABSTRACT FROM AUTHOR]

A conical-diffraction-based cross-dispersed spatial heterodyne spectrometer (CDCDSHS) is presented. Conical diffraction is introduced, and one grating in the SHS is rolled around the central normal of its surface to expand the spectral range. The two-dimensional fringes are generated by the longitudinal-dispersion grating and the lateral-dispersion gratings through conical diffraction. Mathematical expressions are given for the parameter of an interferogram with varying spectral features and for the intensity distribution. Two examples are numerically simulated to demonstrate the performance of the spectrometer. The simulations show that the designed spectrometer can limit the interferogram of each spectral feature to be recorded by certain given rows of pixels on the charge-coupled device to avoid multiplexing disadvantages, and it can obtain clear features in each detailed spectrum with a higher signal-to-noise ratio than the conventional SHS while eliminating the need for filters or moving parts. Replacing the lateral-dispersion grating in the designed spectrometer with a mosaic grating can increase the spectral resolution and broaden the detectable spectral range. The designed spectrometer is also compact, very stable, and high-throughput. All mentioned advantages make the CDCDSHS a good prospect in broadband, high-resolution, high-sensitivity spectral measurement. [ABSTRACT FROM AUTHOR]