Active correction of aperture discontinuities - optimized stroke minimization II: optimization for future missions

TL;DR

This paper introduces optimization tools for the ACAD-OSM technique, enhancing the correction of aperture discontinuities in coronagraphs, crucial for future large telescopes aiming to image exoplanets.

Contribution

It provides a detailed analysis of deformable mirror configurations to optimize ACAD-OSM performance for upcoming space and ground-based telescopes.

Findings

Optimal deformable mirror setup improves contrast and throughput.

Proper configuration minimizes deformable mirror strokes.

Tools for designing future coronagraphic instruments are developed.

Abstract

High-contrast imaging and spectroscopy provide unique constraints for exoplanet formation models as well as for planetary atmosphere models. Instrumentation techniques in this field have greatly improved over the last two decades, with the development of stellar coronagraphy, in parallel with specific methods of wavefront sensing and control. Next generation space- and ground-based telescopes will allow the characterization cold solar-system like planets for the first time and maybe even in situ detection of bio-markers. However, the growth of primary mirror diameters, necessary for these detection, comes with an increase of their complexity (segmentation, secondary mirror features). These discontinuities in the aperture can greatly limit the performance of coronagraphic instruments. In this context, we introduced a new technique, Active Correction of Aperture Discontinuities - Optimized Stroke Minimization (ACAD-OSM), to correct for the diffractive effects of aperture discontinuities in the final image plane of a coronagraph, using deformable mirrors. In this paper, we present several tools that can be used to optimize the performance of this technique for its application to future large missions. In particular, we analyze the influence of the deformable setup (size and separating distance) and found that there is an optimal point for this setup, optimizing the performance of the instrument in contrast and throughput while minimizing the strokes applied to the deformable mirrors. These results will help us design future coronagraphic instruments to obtain the best performance.