Studying focal ratio degradation of optical fibers for Subaru Prime Focus Spectrograph

Jesulino Bispo dos Santos; Antonio Cesar de Oliveira; James Gunn; Ligia Souza de Oliveira; Marcio Vital de Arruda; Bruno Castilho; Clemens Darvin Gneiding; Flavio Felipe Ribeiro; Graham Murray; Daniel J. Reiley; Laerte Sodré Junior; Claudia Mendes de Oliveira

doi:10.1117/12.2056460

arXiv · 1408.3066

Studying focal ratio degradation of optical fibers for Subaru Prime Focus Spectrograph

Jesulino Bispo dos Santos·Antonio Cesar de Oliveira·James Gunn·Ligia Souza de Oliveira·Marcio Vital de Arruda·Bruno Castilho·Clemens Darvin Gneiding·Flavio Felipe Ribeiro·Graham Murray·Daniel J. Reiley·Laerte Sodré Junior·Claudia Mendes de Oliveira

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Abstract

Focal Ration Degradation (FRD) is a change in light angular distribution caused by fiber optics. FRD is important to fiber-fed, spectroscopic astronomical systems because it can cause loss of signal, degradation in spectral resolution, or increased complexity in spectrograph design. Laborat\'orio Nacional de Astrof\'isica (LNA) has developed a system that can accurately and precisely measures FRD, using an absolute method that can also measure fiber throughput. This paper describes the metrology system and shows measurements of Polymicro fiber FBP129168190, FBP127165190 and Fujikura fiber 128170190. Although the FRD of the two fibers are low and similar to one another, it is very important to know the exact characteristics of these fibers since both will be used in the construction of FOCCoS (Fiber Optical Cable and Connectors System) for PFS (Prime Focus Spectrograph) to be installed at the Subaru telescope.

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Jesulino Bispo dos Santos, Antonio Cesar de Oliveira, James Gunn, Ligia Souza de Oliveira, Marcio Vital de Arruda, Bruno Castilho, Clemens Darvin Gneiding, Flavio Felipe Ribeiro, Graham Murray, Daniel J. Reiley, Laerte Sodré Junior, Claudia Mendes de Oliveira. 2014-08-13. Studying focal ratio degradation of optical fibers for Subaru Prime Focus Spectrograph. https://doi.org/10.1117/12.2056460

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