The SPICA Coronagraph Project

We present the latest results of our coronagraphic instrumentation study for the Japanese 3.5m SPICA telescope. Our aim was to validate some of the candidate concepts, amongst which the binary checkerboard mask (Kasdin et al. 2003). This solution benefits from theoretical intrinsic achromaticity, simplicity of its optical implementation which is a key issue since the SPICA telescope is designed to work at cryogenic (4.5K) temperatures. The huge drawback of this solution is its poor so-called inner working angle (IWA) and its overall transmission. This solution, although a clear compromise between performance and complexity, has proven to be a secured backup solution for the SPICA coronagraph.