Patent · US Expired

Method for making colored photochromic prescription ophthalmic lenses

US4498919A · kind A · utility

26Cited by
10References
4Claims
0Family size

Assignee

Inventor

Key dates

Filing dateOct 31, 1983
Grant dateFeb 12, 1985
Priority date
Expiry dateOct 31, 2003

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03C21/002
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Colored photochromic ophthalmic lenses are produced by combining a photochromic cap element having an integrally colored back surface with an ophthalmic crown base element having a prescription-ground back surface, the cap back and base element front surfaces having been finished to a matching standard base curvature, thus providing a cemented assembly exhibiting a selected combination of prescribed vision-correcting and light filtering properties.

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