Patent · US Expired

Bifocal contact lens

US4618229A · kind A · utility

110Cited by
5References
9Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 22, 1983
Grant dateOct 21, 1986
Priority date
Expiry dateJul 22, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02C7/048
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A ballasted multifocal contact lens has a vent for releasing constrictive pressure provided in its lower and ballasted portion. The vent has a surface which tapers from the anterior surface toward the posterior surface to allow the lens to be positioned below the inferior lid. A stabilizing portion is formed on the lens adjacent each side of the vent. The stabilizing portions engage the inferior lid and adjust the lens should it be rotated off axis.

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