Ophthalmic lens
US6116734A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 1998 |
| Grant date | Sep 12, 2000 |
| Priority date | — |
| Expiry date | Aug 5, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/061
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An ophthalmic lens with an aspherical face is provided having a near vision region which is larger in size and wider than that of conventional multifocal lenses, and having reduced aberrations and, notably, astigmatism. Using .DELTA. to signify a difference in mean sphere between the near vision control point and the geometrical center of the lens, this is achieved by making a surface area defined by points less than 20 mm from the geometrical center of the lens, and for which cylinder is comprised between 0.42.DELTA. and 0.84.DELTA. greater than the surface area defined by points less than 20 mm from the geometrical center, and for which cylinder is less than 0.42.DELTA..
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.