Near-infrared wavefront sensing for the VLT interferometer

Stefan Hippler; Wolfgang Brandner; Yann Clénet; Felix Hormuth; Eric Gendron; Thomas Henning; Ralf Klein; Rainer Lenzen; Daniel Meschke; Vianak Naranjo; Udo Neumann; José Ricardo Ramos; Ralf-Rainer Rohloff; Frank Eisenhauer

doi:10.1117/12.789053

arXiv · 0808.1637

Near-infrared wavefront sensing for the VLT interferometer

Stefan Hippler·Wolfgang Brandner·Yann Clénet·Felix Hormuth·Eric Gendron·Thomas Henning·Ralf Klein·Rainer Lenzen·Daniel Meschke·Vianak Naranjo·Udo Neumann·José Ricardo Ramos·Ralf-Rainer Rohloff·Frank Eisenhauer

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Abstract

The very large telescope (VLT) interferometer (VLTI) in its current operating state is equipped with high-order adaptive optics (MACAO) working in the visible spectrum. A low-order near-infrared wavefront sensor (IRIS) is available to measure non-common path tilt aberrations downstream the high-order deformable mirror. For the next generation of VLTI instrumentation, in particular for the designated GRAVITY instrument, we have examined various designs of a four channel high-order near-infrared wavefront sensor. Particular objectives of our study were the specification of the near-infrared detector in combination with a standard wavefront sensing system. In this paper we present the preliminary design of a Shack-Hartmann wavefront sensor operating in the near-infrared wavelength range, which is capable of measuring the wavefronts of four telescopes simultaneously. We further present results of our design study, which aimed at providing a first instrumental concept for GRAVITY.

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Stefan Hippler, Wolfgang Brandner, Yann Clénet, Felix Hormuth, Eric Gendron, Thomas Henning, Ralf Klein, Rainer Lenzen, Daniel Meschke, Vianak Naranjo, Udo Neumann, José Ricardo Ramos, Ralf-Rainer Rohloff, Frank Eisenhauer. 2008-08-12. Near-infrared wavefront sensing for the VLT interferometer. https://doi.org/10.1117/12.789053

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