Infrared, glass polarizer and method
AssigneeCorning Incorporated
InventorsMichael D. Harris, Thomas G. Havens, William E. Horsfall, David J. Kerko
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Abstract
A glass polarizer and a method of making the polarizer, the polarizer being produced from an R2O—Al2O3—B2O3—SiO2 glass containing limited amounts of ZrO2 and TiO2, and having a silver halide liquidus temperature and a rutile liquidus temperature, both temperatures being not over 995° C.
Claims8
A glass polarizer that exhibits excellent polarization in the infrared portion of the spectrum, that contains silver halide particles selected from the group consisting of AgCl, AgBr and AgI, the silver halide particles being elongated and aligned to have an aspect ratio greater than 2:1 after reduction to form silver particles deposited in or upon the elongated silver halide particles, the glass consisting essentially of an R2O—Al2O3—B2O3—SiO2 glass having a composition consisting essentially of 6-20% R2O, wherein the R2O consists of 0.2-5% Li2O, 0-9% Na2O, 0-17% K2O and 0-6% Cs2O, 14-23% B2O3, 5-25% Al2O3, 0-25% P2O5, 20-65% SiO2, 0.15-0.3% Ag, 0.004-0.02% CuO, 0.1-0.25% Cl and 0.1-0.2% Br and containing 4-6% ZrO2, and TiO2 in an amount less than 1% and greater than 0.1%, both by weight, and having both a silver halide and a rutile liquidus temperature, the rutile liquidus temperature being about equal to or below the silver halide liquidus temperature.
A method of making a glass polarizer that exhibits excellent polarizing properties in the infrared region of the radiation spectrum, that contains particles of a silver halide selected from the group consisting of AgCl, AgBr and AgI, and that has both a AgX and a rutile liquidus temperature, the rutile liciuidus temperature being about equal to or below the AgX liquidus temperature, the method including melting and forming a body of a mixed alkali metal oxide aluminoborosilicate glass having a composition consisting essentially of 6-20% R2O, wherein the R2O consists of 0.2-5% Li2O, 0-9% Na2O, 0-17% K2O and 0-6% Cs2O, 14-23% B2O3, 5-25% Al2O3, 0-25% P2O5, 20-65% SiO2, 0.15-0.3% Ag, 0.004-0.02% CuO, 0.1-0.25% Cl and 0.1-02% Br and containing as refractive index enhancing additives 4-6% ZrO2 and TiO2 in an amount less than 1% and greater than 0.1% by weight.
Dependencies are inferred from the claim text.