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arXiv · 1008.4267

The Planar Optics Phase Sensor: a study for the VLTI 2nd Generation Fringe Tracker

Nicolas Blind·Jean-Baptiste LeBouquin·Olivier Absil·Mazen Alamir·Jean-Philippe Berger·Denis Defrère·Philippe Feautrier·Franois Hénault·Laurent Jocou·Pierre Kern·Thomas Laurent·Fabien Malbet·Denis Mourard·Karine Rousselet-Perrault·Alain Sarlette·Jean Surdej·Nassima Tarmoul·Eric Tatulli·Lionel Vincent
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Abstract

In a few years, the second generation instruments of the Very Large Telescope Interferometer (VLTI) will routinely provide observations with 4 to 6 telescopes simultaneously. To reach their ultimate performance, they will need a fringe sensor capable to measure in real time the randomly varying optical paths differences. A collaboration between LAOG (PI institute), IAGL, OCA and GIPSA-Lab has proposed the Planar Optics Phase Sensor concept to ESO for the 2nd Generation Fringe Tracker. This concept is based on the integrated optics technologies, enabling the conception of extremely compact interferometric instruments naturally providing single-mode spatial filtering. It allows operations with 4 and 6 telescopes by measuring the fringes position thanks to a spectrally dispersed ABCD method. We present here the main analysis which led to the current concept as well as the expected on-sky performance and the proposed design.

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Nicolas Blind, Jean-Baptiste LeBouquin, Olivier Absil, Mazen Alamir, Jean-Philippe Berger, Denis Defrère, Philippe Feautrier, Franois Hénault, Laurent Jocou, Pierre Kern, Thomas Laurent, Fabien Malbet, Denis Mourard, Karine Rousselet-Perrault, Alain Sarlette, Jean Surdej, Nassima Tarmoul, Eric Tatulli, Lionel Vincent. 2010-08-25. The Planar Optics Phase Sensor: a study for the VLTI 2nd Generation Fringe Tracker. https://doi.org/10.1117/12.857114

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