Patent · US Expired

Multifocal corneal contact lens pair

US5812236A · kind A · utility

6Cited by
28References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 15, 1996
Grant dateSep 22, 1998
Priority date
Expiry dateNov 15, 2016

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02C7/042
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A pair of multifocal contact lenses customized for a patient. A first corneal contact lens and a second corneal contact lens each have an anterior side with a power curve defined in part by (i) a central surface, (ii) an inner annular surface contiguous with the central surface, (iii) a second annular surface contiguous along a radially inner periphery with the inner annular surface, and, optionally, (iv) an outer annular surface contiguous along a radially inner periphery with the second annular surface. Each of the annular surfaces is concentric or coaxial with the central surface. The central surface corresponds to a distance vision correction zone, the second annular surface to a near vision correction zone, and the outer annular surface to a distant vision correction zone. The inner annular surface of the first corneal contact lens corresponds to a long intermediate vision correction zone, while the inner annular surface of the second corneal contact lens corresponds to a short intermediate vision correction zone. To that end, the inner annular surface of the first corneal contact lens and the inner annular surface of the second corneal contact lens have substantially differen…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.