Contact lens and process for the manufacture thereof

US5166710A · kind A · utility

Assignee

• Ciba-Geigy · US

Inventors

• Peter Hofer · Liestal, CH
• Peter Hagmann · Erlenbach a.Main, DE
• Martin Reichner · Aschaffenburg, DE
• Peter Herbrechtsmeier · Königstein, DE

Key dates

• Filing date: Jan 17, 1991
• Grant date: Nov 24, 1992
• Expiry date: Jan 17, 2011

Classification

• Technology area (CPC G): Physics
• CPC primary: G02C7/048
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A contact lens that consists of gas-permeable, especially oxygen-permeable, lens material and has a supporting edge which rests on the sclera and is covered at least partially by both eyelids and absorbs the forces acting on the lens as the lid closes, the rear face of the lens in the region of the cornea being spaced from the surface of the cornea. By ensuring the exchange of lachrymal fluid between the contact lens and the surface of the eye, metabolic products are transported away and the supply of oxygen to the cornea is assisted. For that purpose, channels may be provided on the lens or the lens may be caused to rotate.