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. 11, 1990
Filed:
Jan. 22, 1990
Applicant:
Inventors:
Assignee:
Essilor International, Cie Generale d'Optique, Creteil Cedex, FR;
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
G02C / ; A61F / ;
U.S. Cl.
CPC ...
351161 ; 623-5 ; 623-6 ;
Abstract
The proximity P of a simultaneous vision optical lens for correcting presbyopia is defined as the reciprocal of the distance D at which a light ray parallel to and at a distance h from its axis crosses the axis after passing through the lens. The curve representing the proximity P of the lens lies between a lower envelope curve P.sub.inf and an upper envelope curve P.sub.sup satisfying the following equations: