Concentric aspheric multifocal lens designs
US5715031A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 4, 1995 |
| Grant date | Feb 3, 1998 |
| Priority date | — |
| Expiry date | May 4, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/06
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Concentric aspheric multifocal lens designs are disclosed which use a combination of an aspheric front surface, which results in aberration reduction and contrast vision enhancement, along with a concentric multifocal back surface, to produce a lens design which affords clear vision at a distance and also near without a loss in contrast which is generally typical of prior art simultaneous vision, concentric multifocal lens designs. The aspheric surface improves the modulation transfer function (MTF) of the lens eye combination which improves the focus and contrast of both distance and near images. The design form is valid for contact lenses and intraocular lenses.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.