Patent ID: 6333826
Filing Date: 2001-12-25
Classification: G02B

Abstract:
An optical system comprising:a convex primary reflector having radial symmetry,said primary reflector being in optical communication with a great circle surrounding it, said great circle being perpendicular to the optical axis of said primary reflector,said primary reflector having sufficient curvature to be in optical communication with a substantial area in front and behind the plane of said great circle,said primary reflector having an optically transparent central zone,a secondary reflector having radial symmetry,said secondary reflector being coaxially disposed in front of said primary reflector,said secondary reflector having its reflective surface facing the reflective surface of said primary reflector,said secondary reflector being in optical communication with said great circle surrounding said primary reflector and said area in front and behind the plane of said great circle by means of reflection from said primary reflector,whereby said optical system produces a virtual image of said great circle and said area above and below its plane, said virtual image being annular,said virtual image being visible from a vantage point behind said optically transparent central zone of said primary reflector due to said vantage point being in optical communication with said great circle and said area in front and behind the plane of said great circle by means of reflection from said secondary reflector and said primary reflector,means for mounting said secondary reflector and said primary reflector,said means providing a protective darkened shield around the perimeter of said secondary reflector, said shield also acting as a light baffle,said means for mounting providing stable support and alignment of said primary reflector and said secondary reflector without causing deformation thereof,said means for mounting providing for attachment of said optical system to an article having a focal surface,said mounting means not relying on the structure of said primary reflector surface substrate to support said article,said mounting means facilitating use of said optical system in any orientation,said article being associated with a refracting lens system, said refracting lens system being disposed coaxial to said optical system, both being associated with the formation of a real image of said virtual image at said focal surface,whereby said optical system combined with said article facilitates the geometric conversion of said great circle and said area in front and behind the plane of said great circle into a real annular image at the focal surface of said article and the geometric conversion of a two dimensional annular image into a three dimensional projected image.