Share Email Print

Proceedings Paper

Efficiently mating fibers to spectrographs
Author(s): Jean P. Brodie; R. Hank Donnelly; Harland W. Epps; Matthew V. Radovan; William W. Craig
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

We describe the conversion of an existing f/8 Cassegrain spectrograph to a floor-mounted spectrograph fed by 94 fibers from the f/5 prime focus of the Shane 3-meter telescope at Lick Observatory. The spectrography forms part of the automated Multi- Object Spectrograph system developed as a collaboration between UCO/Lick Observatory and the Lawrence Livermore National Laboratory. Fibers from a robotic fiber-positioner at prime focus degrade the f/5.5 beam from the telescope (after it has passed through a wide-field prime focus corrector) into roughly a f/4.5 beam. If the 4/8 spectrograph were fed directly with this f/4.5 beam approximately 68% of the light would be lost. A simple optical system has been designed that converts the light from the fibers into the f/ratio expected by the spectrograph. The conversion optics are mounted at the entrance to the spectrograph. We describe focal ratio degradation tests of a variety of optical fibers and the design of the `pseudoslit' which mounts the fibers in a line at the input to the conversion optics.

Paper Details

Date Published: 1 June 1994
PDF: 10 pages
Proc. SPIE 2198, Instrumentation in Astronomy VIII, (1 June 1994); doi: 10.1117/12.176747
Show Author Affiliations
Jean P. Brodie, UCO/Lick Observatory (United States)
R. Hank Donnelly, UCO/Lick Observatory (United States)
Harland W. Epps, UCO/Lick Observatory (United States)
Matthew V. Radovan, UCO/Lick Observatory (United States)
William W. Craig, Lawrence Livermore National Lab. (United States)

Published in SPIE Proceedings Vol. 2198:
Instrumentation in Astronomy VIII
David L. Crawford; Eric R. Craine, Editor(s)

© SPIE. Terms of Use
Back to Top