Patent ID: 6437857
Filing Date: 2002-08-20
Classification: G01M

Abstract:
A variable field angle and test pattern spatial frequency optical assemblage for testing a lens, said lens having a plurality of field angles characteristic of the magnification of the lens being tested, said assemblage comprising:a source of illumination for emitting light; a rotatable platform for supporting a plurality of spatially separated test patterns, said rotatable platform being capable of rotatably positioning any one of said plurality of test patterns in a predetermined optical path for varying said spatial frequency of said test pattern; a collimating lens arranged in said predetermined optical path for receiving light transmitted through said any one of said plurality of test patterns and converting said light to a collimated array of light rays; a reflecting surface arranged in said predetermined optical path for receiving said collimated array of light rays, said reflecting surface being capable of translational and rotational movements about an axis defined by said predetermined optical path for reflecting and then directing the collimated array of light rays through said lens being tested thereby forming an image, and wherein said reflecting surface redirects said collimated array of light rays at an angle characteristic of the magnification of the lens being tested; and, a detector arranged proximate to said image for detecting said image.