High-Contrast Testbeds for Future Space-Based Direct Imaging Exoplanet Missions

TL;DR

This paper reviews the current status of eight optical testbeds in the US and France that validate technologies for high-contrast imaging of exo-Earths, focusing on coronagraphs and wavefront correction for future space missions.

Contribution

It provides an overview of active testbeds and experimental validation efforts for high-contrast imaging technologies crucial for upcoming space-based exoplanet missions.

Findings

Laboratory demonstration of high-contrast performance for off-axis telescopes

Development of technologies for segmented and on-axis telescopes

Parallel analysis of multiple instrument architectures

Abstract

Instrumentation techniques in the field of direct imaging of exoplanets have greatly advanced over the last two decades. Two of the four NASA-commissioned large concept studies involve a high-contrast instrument for the imaging and spectral characterization of exo-Earths from space: LUVOIR and HabEx. This whitepaper describes the status of 8 optical testbeds in the US and France currently in operation to experimentally validate the necessary technologies to image exo-Earths from space. They explore two complementary axes of research: (i) coronagraph designs and manufacturing and (ii) active wavefront correction methods and technologies. Several instrument architectures are currently being analyzed in parallel to provide more degrees of freedom for designing the future coronagraphic instruments. The necessary level of performance has already been demonstrated in-laboratory for clear off-axis telescopes (HabEx-like) and important efforts are currently in development to reproduce this accomplishment on segmented and/or on-axis telescopes (LUVOIR-like) over the next two years.