The Terrestrial Planet Finder Coronagraph optical surface requirements

Abstract

We derive the requirements on the surface height uniformity and reflectivity uniformity of the Terrestrial Planet Finder Coronagraph telescope and instrument optics for spatial frequencies within and beyond the spatial control bandwidth of the wave front control system. Three different wave front control systems are considered: a zero-path difference Michelson interferometer with two deformable mirrors at a pupil image; a sequential pair of deformable mirrors with one placed at a pupil image; and the Visible Nuller spatially-filtered controller. We show that the optical bandwidth limits the useful outer working angle.