Variable spectacle lens
US6040947A · kind A · utility
112Cited by
6References
26Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jun 9, 1998 |
| Grant date | Mar 21, 2000 |
| Priority date | — |
| Expiry date | Jun 9, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C2202/16
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A liquid-filled variable focal length lens of the type which has a distensible membrane as one of the lens surfaces, and a membrane support member to support the perimeter of the free area of the membrane. By using a membrane support member having a toroidally shaped portion, the membrane is supported such that it has a circular free area irrespective of the shape of the perimeter of the lens. The cross sectional shape of the toroidal portion of the support member is preferably approximately an arc of a circle, and the perimeter of the free area of the membrane is maintained tangent thereto.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.