High-contrast imaging in wide spectral band with a self-coherent camera and achromatic coronagraphs

摘要

Direct imaging of exoplanets is very attractive but challenging. It requires high angular resolution and very high-contrast imaging. One solution is the use of coronagraphs behind the adaptive optics of large telescopes. Unfortunately, optics of space telescope and ground telescope introduce quasi-static aberrations which strongly limit the quality of the final image and a dedicated stage of adaptive optics is required. We proposed a self-coherent camera (SCC) in 2006 and we obtained contrast levels of ≈ 2 10~(-8) at a few λ_0/D at 638 nm in laboratory. In this paper, we explain how to achromatize the SCC. We present laboratory performance in wide spectral band ≈ 5 - 10 % bandpass.