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arXiv · 1607.02494

Optimal non-circular fiber geometries for image scrambling in high-resolution spectrographs

Julian Stürmer·Christian Schwab·Stephan Grimm·Andre Kalide·Adam P. Sutherland·Andreas Seifahrt·Kay Schuster·Jacob L. Bean·Andreas Quirrenbach
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Abstract

Optical fibers are a key component for high-resolution spectrographs to attain high precision in radial velocity measurements. We present a custom fiber with a novel core geometry - a 'D'-shape. From a theoretical standpoint, such a fiber should provide superior scrambling and modal noise mitigation, since unlike the commonly used circular and polygonal fiber cross sections, it shows chaotic scrambling. We report on the fabrication process of a test fiber and compare the optical properties, scrambling performance, and modal noise behavior of the D-fiber with those of common polygonal fibers.

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Julian Stürmer, Christian Schwab, Stephan Grimm, Andre Kalide, Adam P. Sutherland, Andreas Seifahrt, Kay Schuster, Jacob L. Bean, Andreas Quirrenbach. 2016-07-08. Optimal non-circular fiber geometries for image scrambling in high-resolution spectrographs. https://doi.org/10.1117/12.2234552

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