Contact lens and the method of manufacturing thereof
US4890911A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 1988 |
| Grant date | Jan 2, 1990 |
| Priority date | — |
| Expiry date | Jul 11, 2008 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31935
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
The invention pertains to a new design of contact lenses and to the method of their manufacturing. The contact lens comprising a carrier portion and a hydrophilic supporting portion mediating the contact of the lens with the eye surface, wherein both these parts are made from different materials, with the supporting portion being divided into two or more independent pieces protruding above the concave surface of the lens and lead from the lens circumference towards the lens center which is left free, with gaps being provided between individual pieces. The supporting part is made from a water-swelling synthetic crosslinked hydrogel which has, in the state of full swelling with physiological saline, a swelling capacity of about 40 to 95 percent, whereas the carrier optical portion is made from a transparent material having a modulus of elasticity at least twice that of the modulus of elasticity of the supporting portion. The supporting portion forms a gap of at least 0.01 mm between the eye surface and the uncovered part of the lens.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.