Patent · US Expired

Transparent photochromic article including an anti-reflection surface coating

US6175450A · kind A · utility

75Cited by
7References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 10, 1998
Grant dateJan 16, 2001
Priority date
Expiry dateNov 10, 2018

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC03C2217/734
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A transparent photochromic article including a transparent substrate including a photochromic material; and an anti-reflection surface coating thereon, produced with a plurality of overlapping layers incorporating, alternatively a first and second material having respectively higher and lower refractive indices, the anti-reflection coating including; a first layer including said first material having an optical thickness of about 20 to 45 nm; a second layer including said second material having an optical thickness of about 25 to 45 nm; a third layer including said first material having an optical thickness of about 220 to 250 nm; and a fourth layer including said second material having an optical thickness of about 95-115 nm.

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