Patent ID: 6137641
Filing Date: 2000-10-24
Classification: G01J,G02B

Abstract:
A method for increasing astigmatism in an optical system, comprising the steps of:providing a substantially symmetrical spherical mirror including a curved surface intersected substantially at right angles by a first plane, and a second plane substantially perpendicular to said first plane and to said curved surface, said first plane aligned with a plane of incidence of said spherical mirror, said plane of incidence including incident light beams and reflected light beams;providing off-axis beams of light onto said spherical mirror causing astigmatism in said reflected light beams:providing a plurality of light receivers;bending said spherical mirror on at least two bending surfaces in said first plane to add a selected amount of curvature to said spherical mirror in said first plane; andsupporting of said spherical mirror on at least two support surfaces in said second plane to subtract said selected amount of curvature from said spherical mirror in said second plane;said bending and supporting steps controlling separation between a sagittal image and a tangential image formed by said spherical mirror and increasing said astigmatism introduced by said spherical mirror increasing separation between tangential and saggital foci to increase height of the tangential image to substantially simultaneously illuminate said plurality of light receivers.