Differential thickness contact lens with compensation for differential shrinkage and method of manufacturing same
US6234629A · kind A · utility
13Cited by
13References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Dec 21, 1998 |
| Grant date | May 22, 2001 |
| Priority date | — |
| Expiry date | Dec 21, 2018 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG02C7/04
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A contact lens and a method of manufacturing a contact lens having areas of different thickness, the contact lens being compensated for differential shrinkage during the manufacturing process. The unwanted toricity induced by the differential shrinkage caused by a particular manufacturing process is experimentally determined, both in terms of angular position and power. The lens compensation is achieved by providing an equal and opposite power to the unwanted toricity induced by the manufacturing process.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.