Translator Disclaimer
1 June 1994 Efficiently mating fibers to spectrographs
Author Affiliations +
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.
© (1994) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Jean P. Brodie, R. Hank Donnelly, Harland W. Epps, Matthew V. Radovan, and William W. Craig "Efficiently mating fibers to spectrographs", Proc. SPIE 2198, Instrumentation in Astronomy VIII, (1 June 1994);


Back to Top