High-resolution, flat-field, plane-grating, f/10 spectrograph with off-axis parabolic mirrors

Abstract

A high-resolution, flat-field, plane-grating, f/10 spectrometer based on the novel design proposed by Gil and Simon [Appl. Opt. 22, 152 (1983)] is demonstrated. The spectrometer design employs off-axis parabolic collimation and camera mirrors in a configuration that eliminates spherical aberrations and minimizes astigmatism, coma, and field curvature in the image plane. In accordance with theoretical analysis, the performance of this spectrometer achieves a high spatial resolution over the large detection area, which is shown to be limited only by the quality of its optics and their proper alignment within the spatial resolution of a 13 microm x 13 microm pixelated CCD detector. With a 1500 lines/mm grating in first order, the measured spectral resolving power of lambda/Dlambda = 2.5(+/-0.5) x 10(4) allows the clear resolution of the violet Ar(I) doublet at 419.07 and 419.10 nm.

The Daniel K. Inouye Solar Telescope (DKIST) Cryogenic Near-Infrared Spectro-Polarimeter

“…As one of the first-light facility instruments of DKIST, the Cryo-NIRSP is a powerful and versatile tool for the study of our Sun that enables frontier diagnostics in the infrared spectrum at wavelengths up to 5 µm. As showcased here, early operations of Cryo-NIRSP are already underway, as is the acquisition of the first science data in support of experiments proposed by the solar research community (Tritschler et al, 2023). Data-calibration strategies are currently being refined in support of the Level 1 pipeline at the DKIST Data Center (Davey et al, 2023).…”

“…The size of the cryostat is always a main consideration when designing a cryogenic instrument and therefore we made every effort to keep the volume as small as possible. The Cryo-NIRSP spectrograph is based on a concept published by Gil and Simon (1983) and first implemented by Schieffer et al (2007). The design is fully reflective for high throughput and broad spectral coverage.…”

Advanced astigmatism-corrected tandem Wadsworth mounting for small-scale spectral broadband imaging spectrometer

“…First, when the spectrometer is applied to faint light detection such as extreme or farultraviolet ionosphere observation by satellite, it usually adopts the off-axis parabolic mirror as the telescope [13]. The form of the telescope guarantees the required optical energy transmission efficiency.…”