Patent · US Expired

Segmented multifocal contact lens

US5198844A · kind A · utility

72Cited by
2References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 10, 1991
Grant dateMar 30, 1993
Priority date
Expiry dateJul 10, 2011

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S425/808
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A multifocal refractive lens to focus light on the retina of the eye and method of making. The lens is comprised of a plurality of segments, alternating segments having different optical powers. At least for distance vision and another for near. The lens of the invention does not require orientation to produce adequate far and near vision and normal steroscoptic effect. One or both of the segments having the optical powers may have aspherical lens surface. Preferably, the lens has at least one aspherical lens surface and the segments are divided by an arcuate path going from the center of the lens to edge. Such a lens is manufactured by taking lens molds and cutting the molds from the edge through the center to the opposite edge along a predetermined path. The molds are cut so that the segments produced are interchangable and can be fitted together to make a mold that can produce the multifocal refractive contact lens by molding.

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