An apodizing phase plate coronagraph for VLT/NACO

TL;DR

This paper introduces a specialized coronagraphic optic for VLT/NACO that enhances direct imaging of exoplanets by suppressing diffraction over a specific wavelength range without requiring a focal mask.

Contribution

The paper presents a novel apodizing phase plate coronagraphic optic optimized for 4.05 microns, achieving high contrast imaging without focal plane masks.

Findings

Achieves 10 magnitudes of contrast at 0.2 arcseconds.

Suppresses diffraction from 1.8 to 7 lambda/D.

Operates effectively at 4.05 microns.

Abstract

We describe a coronagraphic optic for use with CONICA at the VLT that provides suppression of diffraction from 1.8 to 7 lambda/D at 4.05 microns, an optimal wavelength for direct imaging of cool extrasolar planets. The optic is designed to provide 10 magnitudes of contrast at 0.2 arcseconds, over a D-shaped region in the image plane, without the need for any focal plane occulting mask.