Share Email Print
cover

Proceedings Paper

The design of dispersing elements for a highly segmented, very wide-field spectrograph
Format Member Price Non-Member Price
PDF $14.40 $18.00
cover GOOD NEWS! Your organization subscribes to the SPIE Digital Library. You may be able to download this paper for free. Check Access

Paper Abstract

Wide field spectrograph at the largest optical telescopes will be decisive to address the main open questions in modern astrophysics. The key feature of this instrument is the modular concept: the spectrograph is the combination of about one thousand identical small cameras, each carrying a few slits and operating at low to moderate spectral resolution, to be illuminated at the Cassegrain focus of an existing 8m class telescope. The dispersing element to be used in these small cameras has to satisfy some requirements in term of efficiency, resolution, size, small series production. Moreover the cameras have to work both in imaging and spectroscopy modes, therefore a GRISM configuration of the dispersing element is suitable. Based on these considerations, we have focused our attention to Volume Phase Holographic Gratings (VPHGs) since they show large peak efficiency in the target spectral range (400-800 nm), they can be arranged in a GRISM configuration reaching relative large resolution. The main constrains concern the available room for the dispersing element, indeed the camera design is very compact. As a consequence, slanted VPHGs are studied and optimized in combination with normal and Fresnel prisms.

Paper Details

Date Published: 20 July 2010
PDF: 10 pages
Proc. SPIE 7735, Ground-based and Airborne Instrumentation for Astronomy III, 77357M (20 July 2010); doi: 10.1117/12.857689
Show Author Affiliations
Andrea Bianco, INAF, Osservatorio Astronomico di Brera (Italy)
Dario Maccagni, INAF, Istituto di Astrofisica Spaziale e Fisica Cosmica (Italy)
Roberto Ragazzoni, INAF, Osservatorio Astronomico di Padova (Italy)
Adriano Fontana, INAF, Osservatorio Astronomico di Roma (Italy)
Andrea Baruffolo, INAF, Osservatorio Astronomico di Padova (Italy)
Marco Dima, INAF, Osservatorio Astronomico di Padova (Italy)
Andrea Di Paola, INAF, Osservatorio Astronomico di Roma (Italy)
Jacopo Farinato, INAF, Osservatorio Astronomico di Padova (Italy)
Giorgia Gentile, INAF, Osservatorio Astronomico di Padova (Italy)
Emanuele Giallongo, INAF, Osservatorio Astronomico di Roma (Italy)
Demetrio Magrin, INAF, Osservatorio Astronomico di Padova (Italy)
Fernando Pedichini, INAF, Osservatorio Astronomico di Roma (Italy)
Roberto Speziali, INAF, Osservatorio Astronomico di Roma (Italy)
Vincenzo Testa, INAF, Osservatorio Astronomico di Roma (Italy)


Published in SPIE Proceedings Vol. 7735:
Ground-based and Airborne Instrumentation for Astronomy III
Ian S. McLean; Suzanne K. Ramsay; Hideki Takami, Editor(s)

© SPIE. Terms of Use
Back to Top