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:
Dec. 21, 1993
Filed:
Oct. 28, 1992
Claude Pedrono, Briis-sour-Forges, FR;
Essilor International (Compagnie Generale d'Optique), Creteil Cedex, FR;
Abstract
The lens has an aspherical surface having a zone for far vision, a zone for near vision, and between these two zones, a zone for intermediate vision, with a meridian curve along which the curvature of the surface varies progressively and which is inclined from top to bottom towards the nose side of the lens, at least in the intermediate zone. The portion of the meridian curve situated in the intermediate and near zones includes a segment at an angle .alpha. to the vertical where the value of .alpha. is an increasing function of the power addition A of the lens. In a horizontal and vertical system of coordinates, a point of the segment has an ordinate whose value is also an increasing function of the power addition A. At said point, the mean sphere value of the surface corresponds to a power addition lying in the range 0.8 to 0.92 times the nominal power addition of the lens.