Process for making multifocal photochromic ophthalmic lens
US4017292A · kind A · utility
20Cited by
1References
5Claims
0Family size
Assignee
Inventor
Key dates
| Filing date | Jan 15, 1976 |
| Grant date | Apr 12, 1977 |
| Priority date | — |
| Expiry date | Jan 15, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/06
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
Multifocal photochromic opthalmic lenses are produced by nucleating potentially photochromic major lens blanks through heat treatment, combining the nucleated blanks with compatible button or segment glasses, and fusing the combined glasses at temperatures suitable for achieving both fusion and the simultaneous development of full photochromic properties in the previously nucleated major lens blanks.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.