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arXiv · 1810.03627

DOTIFS: fore-optics and calibration unit design

Haeun Chung·A. N. Ramaprakash·Pravin Khodade·Chaitanya V. Rajarshi·Sabyasachi Chattopadhyay·Pravin A. Chordia·Amitesh Omar·Changbom Park
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Abstract

We present fore-optics and calibration unit design of Devasthal Optical Telescope Integral Field Spectrograph (DOTIFS). DOTIFS fore-optics is designed to modify the focal ratio of the light and to match its plate scale to the physical size of Integral Field Units (IFUs). The fore-optics also delivers a telecentric beam to the IFUs on the telescope focal plane. There is a calibration unit part of which is combined with the fore-optics to have a light and compact system. We use Xenon-arc lamp as a continuum source and Krypton/Mercury-Neon lamps as wavelength calibration sources. Fore-optics and calibration unit shares two optical lenses to maintain compactness of the overall subsystem. Here we present optical and opto-mechanical design of the calibration unit and fore-optics as well as calibration scheme of DOTIFS.

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Haeun Chung, A. N. Ramaprakash, Pravin Khodade, Chaitanya V. Rajarshi, Sabyasachi Chattopadhyay, Pravin A. Chordia, Amitesh Omar, Changbom Park. 2018-10-08. DOTIFS: fore-optics and calibration unit design. https://doi.org/10.1117/12.2312394

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