OPTICAL GLASS, OPTICAL GLASS BLANK, GLASS MATERIAL FOR PRESS MOLDING USE, OPTICAL ELEMENT, AND METHODS RESPECTIVELY FOR PRODUCING SAID PRODUCTS

摘要

One embodiment of the present invention relates to an optical glass which has such a glass composition that the content of P2O5 is 20 to 34 mass%, the content of B2O3 is more than 0 mass% and 10 mass% or less, the mass ratio (B2O3/P2O5) falls within the range from 0 to 0.39 exclusive, the mass ratio [TiO2/(TiO2+Nb2O5+WO3+Bi2O3+Ta2O5)] falls within the range from 0.059 to 0.180 and the mass ratio [(P2O5+B2O3+SiO2)/(Na2O+K2O+Li2O)] falls within the range from 1.39 to 1.80 in terms of oxide contents, and which has a refractive index (nd) falling within the range from 1.78 to 1.83 and an Abbe's number (νd) falling within the range from 20 to 25.