Abstract: A missile seeker. The inventive missile seeker includes a dome within which a novel optical arrangement is retained. The optical arrangement includes a first prism mounted for rotation about an optical axis and a second prism mounted for rotation about the optical axis. In the illustrative embodiment, the first and second prisms are Risley prisms. In addition, the illustrative implementation includes a first motor arrangement for rotating the first prism about the optical axis and a second motor arrangement for rotating the second prism about the optical axis. A controller is provided for activating the first and second motors to steer the beam at an angle &phgr; and nod the beam at an angle &thgr;. In a specific implementation, the first prism and/or the second prism have at least two surfaces contoured to correct for optical aberration. A teaching is provided to contour the surfaces to correct for astigmatism, coma, trefoil and other non-rotationally symettric abberation.

Abstract: A steerable optical arrangement. The inventive arrangement includes a first prism mounted for rotation about an optical axis and a second prism mounted for rotation about the optical axis. In accordance with the inventive teachings, the first prism and/or the second prism have at least one surface contoured to correct for optical aberration. In the illustrative embodiment, the first and second prisms are Risley prisms. In addition, the illustrative implementation includes a first motor arrangement for rotating the first prism about the optical axis and a second motor arrangement for rotating the second prism about the optical axis. A controller is provided for activating the first and second motors to steer the beam at an angle &phgr; and nod the beam at an angle &thgr;. At least two surfaces at least one prism is contoured to correct for astigmatism, coma, trefoil and other non-rotationally symmetric aberration.