Progressive ophthalmic lens
US4461550A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 22, 1981 |
| Grant date | Jul 24, 1984 |
| Priority date | — |
| Expiry date | Apr 22, 2001 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/16
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A progressive opthalmic lens is disclosed which has an upper part of constant refractive power for distance vision and a lower part of progressively variable refractive power for near vision. In order to increase the effective field of intermediate vision while providing smooth transition between the upper and lower parts of the lens for the user, an additional segment providing a local addition of refractive power is superposed on at least a portion of the progressive variable power zone of the lens. The additional segment may comprise an insert or a protuberance on the progressive portion which may be formed as a surface film on a blank base or substrate. The additional segment may have constant refractive power or include a progressively variable refractive power area.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.