Focal plane wavefront sensing and control strategies for high-contrast imaging on the MagAO-X instrument

TL;DR

This paper discusses wavefront sensing and control strategies for the MagAO-X instrument, combining focal plane techniques with traditional AO to achieve high-contrast imaging in visible to near-IR wavelengths.

Contribution

It introduces the implementation and simulation of focal plane wavefront sensing methods, LOWFS and LDFC, integrated with the MagAO-X system for improved high-contrast imaging.

Findings

Simulation results demonstrate effectiveness of LOWFS and LDFC techniques.

Laboratory experiments validate the algorithms with a vAPP coronagraph.

Achieved raw contrast level of 6 x 10^-5 in simulations and lab tests.

Abstract

The Magellan extreme adaptive optics (MagAO-X) instrument is a new extreme adaptive optics (ExAO) system designed for operation in the visible to near-IR which will deliver high contrast-imaging capabilities. The main AO system will be driven by a pyramid wavefront sensor (PyWFS); however, to mitigate the impact of quasi-static and non-common path (NCP) aberrations, focal plane wavefront sensing (FPWFS) in the form of low-order wavefront sensing (LOWFS) and spatial linear dark field control (LDFC) will be employed behind a vector apodizing phase plate (vAPP) coronagraph using rejected starlight at an intermediate focal plane. These techniques will allow for continuous high-contrast imaging performance at the raw contrast level delivered by the vAPP coronagraph 6 x 10^-5. We present simulation results for LOWFS and spatial LDFC with a vAPP coronagraph, as well as laboratory results for both algorithms implemented with a vAPP coronagraph at the University of Arizona Extreme Wavefront Control Lab.