High-Resolution Imaging in the Visible on Large Ground-Based Telescopes

TL;DR

This paper introduces AOLI, a new high-resolution imaging instrument combining lucky imaging and adaptive optics, achieving near-diffraction-limited visible images from ground-based telescopes with full sky coverage.

Contribution

The paper presents a novel instrument design with advanced wavefront sensors and photon counting detectors, enabling unprecedented ground-based high-resolution visible imaging.

Findings

First high-sensitivity, near diffraction-limited visible imaging system from the ground.

Achieves higher resolution than space telescopes in the visible spectrum.

Provides full sky coverage with faint guide stars.

Abstract

Lucky Imaging combined with a low order adaptive optics system has given the highest resolution images ever taken in the visible or near infrared of faint astronomical objects. This paper describes a new instrument that has already been deployed on the WHT 4.2m telescope on La Palma, with particular emphasis on the optical design and the predicted system performance. A new design of low order wavefront sensor using photon counting CCD detectors and multi-plane curvature wavefront sensor will allow virtually full sky coverage with faint natural guide stars. With a 2 x 2 array of 1024 x 1024 photon counting EMCCDs, AOLI is the first of the new class of high sensitivity, near diffraction limited imaging systems giving higher resolution in the visible from the ground than hitherto been possible from space.