Self-coherent camera: first results of a high-contrast imaging bench in visible light

International audienceExtreme adaptive optics and coronagraphy are mandatory for direct imaging of exoplanets. Quasi-static aberrations limit the instrument performance producing speckle noise in the focal plane. We propose a Self-Coherent Camera (SCC) to both control a deformable mirror that actively compensates wavefront error, and calibrate the speckle noise. We create a reference beam to spatially modulate the coronagraphic speckle pattern with Fizeau fringes. In a first step, we are able to extract wavefront aberrations from the science image and correct for them using a deformable mirror. In a second step, we apply a post-processing algorithm to discriminate the companion image from the residual speckle field. To validate the instrumental concept, we developed a high contrast imaging bench in visible light. We associated a SCC to a four quadrant phase mask coronagraph and a deformable mirror (DM) with a high number of actuators (32x32 Boston Michromachines MEMS). We will present this bench and show first experimental results of focal plane wavefront sensing and high contrast imaging. The measurements are compared to numerical simulations