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arXiv · 1009.3474

FFREE: a Fresnel-FRee Experiment for EPICS, the EELT planets imager

Jacopo Antichi·Christophe Vérinaud·Olivier Preis·Alain Delboulbé·Gérard Zins·Patrick Rabou·Jean-Luc Beuzit·Sarah Dandy·Jean-François Sauvage·Thierry Fusco·Emmanuel Aller-Carpentier·Markus Kasper·Norbert Hubin
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Abstract

The purpose of FFREE - the new optical bench devoted to experiments on high-contrast imaging at LAOG - consists in the validation of algorithms based on off-line calibration techniques and adaptive optics (AO) respectively for the wavefront measurement and its compensation. The aim is the rejection of the static speckles pattern arising in a focal plane after a diffraction suppression system (based on apodization or coronagraphy) by wavefront pre-compensation. To this aim, FFREE has been optimized to minimize Fresnel propagation over a large near infrared (NIR) bandwidth in a way allowing efficient rejection up to the AO control radius, it stands then as a demonstrator for the future implementation of the optics that will be common to the scientific instrumentation installed on EPICS.

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Jacopo Antichi, Christophe Vérinaud, Olivier Preis, Alain Delboulbé, Gérard Zins, Patrick Rabou, Jean-Luc Beuzit, Sarah Dandy, Jean-François Sauvage, Thierry Fusco, Emmanuel Aller-Carpentier, Markus Kasper, Norbert Hubin. 2010-09-17. FFREE: a Fresnel-FRee Experiment for EPICS, the EELT planets imager. https://doi.org/10.1117/12.857065

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