Method of making an ophthalmic lens of progressively variable focal power
US4118853A · kind A · utility
77Cited by
5References
7Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Oct 19, 1976 |
| Grant date | Oct 10, 1978 |
| Priority date | — |
| Expiry date | Oct 19, 1996 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T29/49998
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention relates generally to the production of ophthalmic lenses having, on one face, an active zone of progressively variable radius of curvature. According to the invention, when the blank from which such a lens is obtained is being cast, there is formed, on the periphery of its active zone, an edge region or facet extending continuously and circularly right round the said active zone for the subsequent support of the mould which is used to enable a gripper block to be cast on the face of the blank so as to enable a second machining operation to be carried out on the opposite face of the blank.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.