Telescope design for direct imaging of extra-solar planets

We report on the design of a single 1.5-2.0-meter orbiting telescope capable of direct imaging of Jupiter-class planets around solar-type stars at a distance of up to 10 parsecs. Unlike previous designs, our telescope would operate in the visible spectrum, measuring reflected light to maximize angular resolution. The telescope would achieve a contrast of up to 10 orders of magnitude by utilizing a combination of superpolished low-scattering mirror surfaces, Gregorian telescope design with field and Lyot stops, and low-loss apodization to control diffraction. Calculations indicate that the system should reliably detect Jupiter-class planets around solar-class stars at angular separations of 0.5 arcsec. Such a single-telescope system would fit within the constraints of a Discovery-level NASA program and would serve as a pathfinder for large space-based interferometric systems.