Method of manufacturing toric single vision, spherical or aspheric bifocal, multifocal or progressive contact lenses
US5517259A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1994 |
| Grant date | May 14, 1996 |
| Priority date | — |
| Expiry date | Apr 8, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/20
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Methods for providing a contact lens are described. According to a first embodiment, a patient is fitted with an optical preform and the position on the surface of the optical preform corresponding to the center location of the patients's pupil is identified. Then, the optical preform, a volume of polymerizable resin, and a mold comprising a casting zone are arranged, so that the resin occupies at least the intervening space between the mold and the optical preform in the area of the casting zone and so that the casting zone on the mold is aligned to a predetermined position with respect to the position on the surface of the optical preform corresponding to the center of the patient's pupil. Finally, the resin is polymerized to provide a contact lens with an optical modification corresponding to the casting zone. According to another embodiment, a mold having a weight or stabilization zone is selected to provide a resin mass on an optical preform (which can be, for example, toric, bifocal or multifocal, and so forth) sufficient to stabilize the optical preform. The resin mass is provided in a position based, for example, on the axis of cylinder of the finished lens, the orientation…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.