| 摘要 |
[Problem] The transmittance of glass can be dramatically improved as a result of this glass production method. In addition, the amount of rare metal, such as platinum, that melts into glass can be greatly reduced. [Solution] A glass production method whereby the water content in molten glass is increased, in a melting step (i) in which a glass raw material including at least one type of component among TiO2, Nb2O5, WO3, and Bi2O3 is heated inside a melting container and melted, and a molten glass is obtained. |
| 主权项 |
1. An optical glass production method comprising carrying out a procedure to increase a water content in a molten glass during a melting step (i) of a glass raw material including at least one of TiO2, Nb2O5, WO3 and Bi2O3 in a melting container to thereby obtain the molten glass, wherein the optical glass has a total content of TiO2, Nb2O5, WO3 and Bi2O3 of 20 mol % or more and a P2O5 content of 7 to 40 mol %, and the optical glass satisfies at least one selected from a group consisting of the following (a), (b), (c) and (d):
(a) a total amount of P2O5, SiO2, B2O3, TiO2, Nb2O5, WO3, Bi2O3, MgO, CaO, SrO, BaO, ZnO, Li2O, Na2O, K2O, Al2O3, ZrO2, GeO2, TeO2 and Sb2O3 is 90 mol % or more, (b) a glass transition temperature Tg is 541° C. or more, (c) a content of Nb2O5 is 5 mol % or more, and (d) a content of TiO2 is 1 mol % or more. |
