Casting process for plastic lenses
US4191717A · kind A · utility
22Cited by
13References
3Claims
0Family size
Inventor
Key dates
| Filing date | Jan 19, 1978 |
| Grant date | Mar 4, 1980 |
| Priority date | — |
| Expiry date | Jan 19, 1998 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB29L2031/7602
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A process and apparatus particularly suited for casting ophthalmic lenses from a liquid monomer such as "CR-39". The liquid monomer and a catalyst are metered into a plastic lower mold member. A plastic upper mold member is supported by the upper surface of the liquid and by a suspension arrangement which includes a spacer ring and a plurality of ears extending from the upper mold member. The upper mold member is controllably drawn downwardly as the liquid plastic solidifies. Optical surfaces are obtained without polishing or other finishing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.