The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 29, 1988
Filed:
Jul. 24, 1985
Dennis T Grendahl, Excelsior, MN (US);
Other;
Abstract
An intraocular lens including an annular Fresnel lens for implant in the anterior chamber, the posterior chamber or in the cornea of the eye. The Fresnel lens can be made of polymethylmethacrylate (PMMA) or a high index of refraction material. The lens is an annular lens with centers of curvature of different rings receding from the axis according to the distance from the center so as to minimize spherical aberration where the only spherical surface is the central part of the lens, that central part can be plano-convex. A composite material can overlay the Fresnel elements providing a smooth entrant surface. The composite material can be a crystalline or other material which changes index of refraction when excited with electrical power or radiant energy.