Progressive addition lenses
US6149271A · kind A · utility
40Cited by
16References
26Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Oct 23, 1998 |
| Grant date | Nov 21, 2000 |
| Priority date | — |
| Expiry date | Oct 23, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/061
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention provides progressive addition lenses in which lens unwanted astigmatism is reduced and channel width through the intermediate and near vision zones is increased as compared to conventional progressive addition lenses. This result is achieved by combining two or more progressive addition surfaces, which surfaces in combination provide the dioptric add power of the lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.