Abstract

Detection of nonsolar planets is a challenging problem. Due to the planets' faintness relative to the star, it is necessary to suppress the stellar diffracted energy to very low levels. In addition, the planets' proximity to the star requires large diameter optics. This research examines various multiaperture and segmented telescopic systems incorporating Lyot coronagraphs to suppress the stellar diffracted energy and provide the required resolution so that the extrasolar planets can be directly imaged. Because of the phasing tolerances and required contrast ratios, the IR band of 10.5-13.5 µm was examined over a field of view of 0.2-2 arcsec. Various telescopic objectives with the Lyot coronagraph were examined for their ability to suppress the stellar diffracted energy levels. The designs examined were comprised of segmented circular, hexagonal, apodized hexagonal, and rectangular systems. The Lyot coronagraph consists of a Gaussian apodizer at the focal plane of the objective and a Lyot stop at the image plane of the objective.

© 1989 Optical Society of America