Optical filter glasses
AssigneeCorning Incorporated
InventorsDavid J. Kerko, Brent M. Wedding
Life of this patent
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Abstract
This invention is directed to the production of a silver halide-containing glass article essentially free from silver halide crystals exhibiting a bright yellow coloration which strongly attenuates the transmission of ultraviolet radiation and radiation having a wavelength up to about 450 nm, said article having an integral reduced surface layer thereon, the depth of that layer being sufficient to effectively prevent the transmission therethrough of ultraviolet radiation and radiation having a wavelength up to about 450 nm.
Claims2
A silver halide-containing glass article essentially free from silver halide crystals exhibiting a bright yellow coloration which strongly attenuates the transmission of ultraviolet radiation and radiation having a wavelength up to about 450 nm, said article having an integral reduced surface layer thereon, the depth of that layer being sufficient to effectively prevent the transmission therethrough of ultraviolet radiation and radiation having a wavelength up to about 450 nm wherein said glass article consists essentially, expressed in terms of weight percent, of 0-2.5% Li.sub.2 O, 0-9% Na.sub.2 O, 0-17% K.sub.2 O, 0-6% Cs.sub.2 O, 8-20% Li.sub.2 O+Na.sub.2 O+K.sub.2 O+Cs.sub.2 O, 14-23% B.sub.2 O.sub.3, 5-25% Al.sub.2 O, 0-25% P.sub.2 O.sub.5, 20-65% SiO.sub.2, 0.004-0.02% CuO, 0.15-0.3% Ag, 0.1-0.25% Cl, and 0.1-0.2% Br, wherein the molar ratio alkali metal oxides:B.sub.2 O.sub.3 ranges about 0.55-0.85 and the weight ratio Ag:(Cl+Br) ranges about 0.65-0.95.
Dependencies are inferred from the claim text.