Method of making a clear axis, segmented multifocal ophthalmic lens
US5512220A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 14, 1993 |
| Grant date | Apr 30, 1996 |
| Priority date | — |
| Expiry date | May 14, 2013 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S425/808
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A method of making a multifocal refractive lens to focus light on the retina of the eye. The lens includes a plurality of segments, having different optical powers, at least one for distance vision and another for near. The lens does not require orientation to produce adequate far and near vision and normal stereoscopic effect. One or both of the segments having the optical powers may have aspherical lens surface. The central zone of the lens consists of only one lens segment, providing a clear central axis. Segments of the other optical power border the first segment along a path defined by a semi-circle or hyperbola that extends from one point along the periphery of the adjoining segments to another point along the periphery of the adjoining segments.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.