Mary H Sukkar

US Patent:

46145303, Sep 30, 1986

Filed:

Dec 18, 1984

Appl. No.:

6/682905

Inventors:

Mary H. Sukkar - Tulsa OK

International Classification:

C03C 406

US Classification:

65 3011

Abstract:

A step gradient photochromic glass body is produced by illuminating a selected region of a photochromic glass during isothermal heat treatment with light of a specified energy and intensity while shielding the rest of the glass. The regions of glass exposed to this light during heat treatment are arrested in the development of their photochromic properties, while those regions which are simultaneously shielded from light develop their photochromic properties normally. The light gradient across the glass body during heat treatment is effective to provide a similar gradient in photochromic properties thereacross.