A Wavefront Sensor to Detect Dim Objects

Mala Mateen (Air Force Research Laboratory), Olivier Guyon (University of Arizona), Michael Hart (University of Arizona), Johanan Codona (University of Arizona)

Keywords: dim objects, non-linear curvature wavefront sensor, adaptive optics

Abstract:

In this paper we present the progress made towards building the non-linear Curvature wavefront sensor (nlCWFS) to be used in an adaptive optics system for the direct imaging of exoplanets without the use of a laser guide star (LGS). Commonly used wavefront sensors such as the Shack Hartmann wavefront sensor (SHWFS) do a good job of reconstructing high order modes but due to design limitations are poor at reconstructing low order modes. The nlCWFS is able to use the full spatial coherence of the pupil allowing it to reconstruct all spatial frequencies equally well. The nlCWFS senses at the diffraction limit as opposed to the SHWFS which senses at the seeing limit. This awards the nlCWFS a gain in flux of (D/r0)2. In this paper we present results from putting the nlCWFS on the 6.5m MMT Observatory and detail the progress being made to build the nlCWFS for the 1.5 m Air Force Research Laboratory/RDS Optics Division telescope.

Date of Conference: September 9-12, 2014

Track: Adaptive Optics & Imaging

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