Laboratory demonstrations of high-contrast imaging for space coronagraphy

Space coronagraphy is a promising method for direct imaging of planetary systems orbiting the nearby stars. The High Contrast Imaging Testbed is a laboratory facility at JPL that integrates the essential hardware and control algorithms needed for suppression of diffracted and scattered light near a target star that would otherwise obscure an associated exo-planetary system. Stable suppression of starlight by a factor of 5×10 −10 has been demonstrated consistently in narrowband light over fields of view as close as four Airy radii from the star. Recent progress includes the extension of spectral bandwidths to 10% at contrast levels of 2×10 −9 , with work in progress to further improve contrast levels, bandwidth, and instrument throughput. We summarize recent laboratory results and outline future directions. This laboratory experience is used to refine computational models, leading to performance and tolerance predictions for future space mission architectures.