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. 02, 1993
Filed:
Feb. 10, 1992
Leanirith Yean, Longjumeau, FR;
Georges Wajs, Ivry, FR;
Gerard Martin, Antony, FR;
Patrick Guerrero, Lorrez Le Bocage, FR;
Essilor International Cie Generale d'Optique, Creteil Cedex, FR;
Abstract
In a method of manufacturing a transparent polymer material article having a refractive index gradient the polymer base material is caused to absorb a swelling agent including at least a monomer adapted to yield a polymer having a refractive index different than that of the polymer base material. A first preform having a first geometry is formed from the polymer base material sufficiently polymerized for the first preform to be self-supporting. A confinement space is defined between the first preform and an abutment member having facing it a second geometry at least partly different than the first geometry and having a greater volume than the latter. The first preform is brought into contact in the confinement space with a sufficient quantity of swelling agent for the swelling to which it is then subject to cause it to be urged actively into contact with all points of the second geometry. The resulting polymer material is polymerized and the second preform thus obtained is machined, if necessary, to the required final geometry of the required article. The method finds an application in the manufacture of ophthalmic lenses.