A high-contrast coronagraph for earth-like exoplanet direct imaging: design and test

TL;DR

This paper presents a laboratory demonstration of a high-contrast coronagraph capable of achieving the contrast needed for direct imaging of earth-like exoplanets, using innovative phase correction and noise suppression techniques.

Contribution

The study introduces a novel coronagraph design with a liquid crystal array phase corrector and a step-transmission apodized filter, achieving near the contrast required for earth-like exoplanet imaging.

Findings

Achieved a contrast of 1.68 x 10^(-9) at 4 lambda/D in laboratory tests.

Demonstrated potential for direct imaging of Jupiter-like exoplanets.

Showed feasibility of space-based high-contrast coronagraphs for earth-like planets.

Abstract

The high-contrast coronagraph for direct imaging earth-like exoplanet at the visible needs a contrast of 10^(-10) at a small angular separation of 4 lambda/D or less. Here we report our recent laboratory experiment that is close to the limits. The test of the high-contrast imaging coronagraph is based on our step-transmission apodized filter. To achieve the goal, we use a liquid crystal array (LCA) as a phase corrector to create a dark hole based on our dedicated focal dark algorithm. We have suppressed the diffracted and speckle noise near the star point image to a level of 1.68 x 10^(-9) at 4 lambda/D, which can be immediately used for the direct imaging of Jupiter like exoplanets. This demonstrates that high-contrast coronagraph telescope in space has the potentiality to detect and characterize earth-like planets.