Cryogenic IR test of the 4QPM coronagraph

Abstract
We report on the facility we developed at the Observatoire de Meudon to test the Four Quadrant Phase Mask (4QPM) coronagraph in the Infrared (IR) and at low temperature. This facility has been developed in the context of the mid-IR instrument MIRI for the James Webb Space Telescope. Three 4QPM will take place inside MIRI and need to be qualified for space environment. The performance of the coronagraph is in agreement with our expectations from numerical simulations. The peak intensity of the diffraction pattern is reduced by a factor 380, a performance being limited by the chromatic effects and the size of the bench source.