Inventors:
Kelly E. Jones - Salt Lake City UT
Frederick E. Noll - Horseheads NY
Assignee:
Corning Incorporated - Corning NY
International Classification:
C03C 326, C03C 2300
Abstract:
This invention is directed to the preparation of glass articles exhibiting a relatively broad band of high contrast polarizing properties in the infrared region of the radiation spectrum from glasses containing silver halide particles selected from the group consisting of AgCl, AgBr, and AgI. The inventive method comprises the following five general steps:
(a) melting a batch for a glass containing silver and at least one halide selected from the group consisting of chloride, bromide, and iodide;
(b) cooling and shaping said melt into a glass article of a desired configuration;
(c) subjecting said glass article to a temperature at least above the strain point, but not in excess of 75. degree. C. above the softening point of the glass, for a sufficient length of time to cause the generation of silver halide particles therein selected from the group consisting of AgCl, AgBr, and AgI, said particles ranging in size between about 200-5000. ANG. ;
(d) elongating said glass article under stress at a temperature above the annealing point, but below that where said glass exhibits a viscosity of about 10. sup.