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:
Feb. 10, 1976
Filed:
Feb. 27, 1974
Malcolm G Townsley, Park Ridge, IL (US);
Wesley-Jessen Inc., Chicago, IL (US);
Abstract
A process for prescribing and manufacturing contact lenses wherein a first concave curvature is developed on the interior face of the lens in the central optical zone. This concave curvature conforms to a portion of a sphere having a radius equal to the radius of a base curve determined to be suitable for the particular patient. A second concave curvature is developed on the interior face of the lens to provide a bearing zone in surrounding relationship relative to the optical zone. The second curvature conforms to an annulus of a sphere having a radius determined by the slope of the patient's eye at points of contact of the second curvature with the eye. The slope is determined by calculating the eccentricity of the ellipsoidal surface which most closely describes the shape of the patient's eye.