Tricurve optical metal master mold and method of making
US4681295A · kind A · utility
21Cited by
16References
6Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Jul 29, 1985 |
| Grant date | Jul 21, 1987 |
| Priority date | — |
| Expiry date | Jul 29, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T82/10
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
Spherical hydrophilic contact lenses having a characteristic tricurve configuration designed to correct myopia (nearsightedness) are described. The center zone (A1) of the lens is substantially thinner than the periphery (A3) allowing enhanced oxygen transmission and comfortable, increased wearing times while the thicker mid-periphery (A2) imparts necessary integrity and handling characteristics for convenience in manual manipulation. Lenses are molded or cast directly in the desired tricurve configuration using specially designed replica molds made from metal master molds.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.