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arXiv · 1805.09073

Spectrographs with holographic gratings on freeform surfaces: design approach and application for the LUVOIR mission

Eduard Muslimov·Marc Ferrari·Emmanuel Hugot·Jean-Claude Bouret·Coralie Neiner·Simona Lombardo·Gerard Lemaitre·Robert Grange
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Abstract

In the present paper we demonstrate the approach to use a holographic grating on a freeform surface for advanced spectrographs design. On the example POLLUX spectropolarimeter medium-UV channel we chow that such a grating can operate as a cross-disperser and a camera mirror at the same time. It provides the image quality high enough to reach the spectral resolving power of 126 359-133 106 between 11.5 and 195 nm, which is higher than the requirement. Also we show a possibility to use a similar element working in transmission to build an unobscured double-Schmidt spectrograph. The spectral resolving power reaches 2750 for a long slit. It is also shown that the parameters of both the gratings are feasible with the current technologies.

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Eduard Muslimov, Marc Ferrari, Emmanuel Hugot, Jean-Claude Bouret, Coralie Neiner, Simona Lombardo, Gerard Lemaitre, Robert Grange. 2018-05-23. Spectrographs with holographic gratings on freeform surfaces: design approach and application for the LUVOIR mission. https://arxiv.org/abs/1805.09073

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