Patent ID: 6940645

Claim:
A monocentric autostereoscopic optical apparatus for viewing a stereoscopic virtual image comprising a left image to be viewed by an observer at a left viewing pupil and a right image to be viewed by the observer at a right viewing pupil, the apparatus comprising: (a) a left optical system for forming said left image to be viewed at said left viewing pupil, the system comprising: (1) a left image generation system for providing scene content, comprising a left image generator and a left relay lens for forming a left intermediate image; (2) a left projection system comprising a left spherically curved diffusive surface for accepting said left intermediate image, said left spherically curved surface having a center of curvature substantially concentric with a left spherical gradient-index ball lens, said left spherical gradient-index ball lens spaced apart from said left spherically curved diffusive surface such that a left curved image is formed, said left curved image being a real image, a center of curvature of said left curved image coincident with a center of curvature of said left spherical gradient-index ball lens, said left spherical gradient-index ball lens having a left spherical gradient-index ball lens pupil; (b) a right optical system for forming said right image to be viewed at said right viewing pupil, the system comprising: (1) a right image generation system for providing scene content, comprising a right image generator and a right relay lens for forming a right intermediate image; (2) a right projection system comprising a right spherically curved diffusive surface for accepting said right intermediate image, said right spherically curved surface having a center of curvature substantially concentric with a right spherical gradient-index ball lens, said right spherical gradient-index ball lens spaced apart from said right spherically curved diffusive surface such that a right curved image is formed, said right curved image being a real image, a center of curvature of said right curved image coincident with a center of curvature of said right spherical gradient-index ball lens, said right spherical gradient-index ball lens having a right spherical gradient-index ball lens pupil; (c) a curved mirror, said curved mirror having a center of curvature placed optically midway between said left spherical gradient-index ball lens and said right spherical gradient-index ball lens; and (d) a beamsplitter disposed to reflect said left and right curved images toward said curved mirror, said curved mirror disposed to form a virtual stereoscopic image of said left and right curved images, and said curved mirror disposed to form, through said beamsplitter, a real image of said left spherical gradient-index ball lens pupil at said left viewing pupil and a real image of said right spherical gradient-index ball lens pupil at said right viewing pupil.