Glass, optical glass, phosphate optical glass, glass material for polishing, glass material for press molding, and optical element

摘要

[Problem] To provide a phosphate optical glass which has excellent transmissivity and which, through high dispersion, suppresses an increase in the refractive index. Further, to provide an optical element and an optical glass material comprising the phosphate optical glass. [Solution] A phosphate optical glass which has an Abbe number, νd, of 16.70 or lower, a refractive index, nd, of 2.1000 or lower, and which includes P2O5, TiO2 and Nb2O5, wherein, the mass ratio (TiO2/Nb2O5) of the content of TiO2 to the content of Nb2O5 is 0.15 or higher.