摘要 |
An optical glass has a composition including: 40 to 65 mass % of P2O5, and 0 to less than 5 mass % of Li2O+Na2O+K2O. In the optical glass, (MgO+CaO)/(Li2O+Na2O+K2O) which is a ratio of the total content expressed in mass % of MgO and CaO to the total content expressed in mass % of Li2O, Na2O, and K2O, is in a range from 6 to 38.
|