Optical glass for precision molding
AssigneeSumita Optical Glass, Inc.
InventorsKoji Nakahata, Koichi Tsuchiya, Shinobu Nagahama
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Abstract
The present invention provides an optical glass for precision molding, having excellent properties, i.e. yield temperature (At) of at most 550° C., refractive index (nd) of at least 1.83 and Abbe number (νd) of at most 26.0 and further providing a low softening property as well as an improved mass production property with less coloration, which is represented, in term of atoms for making up the glass, by the following chemical composition (wt %) P2O5 14.0 to 31.0% B2O3 0 to 5.0% GeO2 0 to 14.0% Sum of P2O5 + B2O3 + GeO2 14.0 to 35.0% Li2O 0 to 6.0% Na2O 2.5 to 14.0% Sum of Li2O + Na2O 2.5 to 15.0% Nb2O5 22.0 to 50.0% WO3 0 to 30.0% Bi2O3 5.0 to 36.0% BaO 0 to 22.0%.
Claims2
A high refractive index, high dispersion optical glass or precision molding, having a yield temperature (At) of at most 550° C., refractive index (nd) of at least 1.83 and Abbe number (νd) of at most 26.0, which is represented, in term of atoms for making up the glass, by the following chemical composition (wt %):
- P2O5 14.0 to 31.0% B2O3 0 to 5.0% GeO2 0 to 14.0% Sum of P2O5 + B2O3 + GeO2 14.0 to 35.0% Li2O 0 to 6.0% Na2O 2.5 to 14.0% Sum of Li2O + Na2O 2.5 to 15.0% Nb2O5 25.0 to 50.0% WO3 0 to 30.0% Bi2O3 5.0 to 36.0% BaO 0 to 22.0%.
A high refractive index, high dispersion optical glass for precision molding, having a yield temperature (At) of at most 550° C., refractive index (nd) of at least 1.83 and Abbe number (νd) of at most 26.0, which is represented, in term of atoms for making up the glass, by the following chemical composition (wt %):
- P2O5 15.0 to 30.0% B2O3 0 to 4.0% GeO2 0 to 12.0% Sum of P2O5 + B2O3 + GeO2 17.0 to 30.0% Li2O 0 to 5.0% Na2O 5.0 to 13.0% Sum of Li2O + Na2O 5.0 to 14.0% Nb2O5 25.0 to 45.0% WO3 0 to 20.0% Bi2O3 6.0 to 30.0% BaO 0 to 15.0%.
Dependencies are inferred from the claim text.