Progressive multifocal ophthalmic lens
US5719658A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 14, 1995 |
| Grant date | Feb 17, 1998 |
| Priority date | — |
| Expiry date | Jul 14, 2015 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/061
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
In a progressive multifocal ophthalmic lens providing excellent performance in the far vision region, good width of the near vision region and gentle progression in the intermediate vision region therebetween, the far vision region comprises an angular sector defined by two half-lines that intersect at the geometrical center of the lens forming an upwardly-directed angular segment with an included angle of preferably more than 145.degree. in which all points have a cylinder less than A/2 diopters, and constraints are applied governing the gentleness of progression in the intermediate vision region and the relative width of the near vision region.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.