| 摘要 |
An optical glass which is characterized as comprising, based on mass %, 60 to 65 % of SiO2, 14 to 19 % of B2O3, 5 to 9 % of Al2O3, 4 to 8 % of Li2O, 0 to 4 % of Na2O, 6.6 to 9 % of K2O (with the proviso that the sum of the amounts of Li2O, Na2O and K2O is 11 to 16 %), 0.05 to 1 % of TiO2, 0.1 to 4 % of ZnO and 0 to 2 % of Sb2O3, and having a refractive index (nd) of 1.47 to 1.53 and an Abbe value ( nu d) of 60 to 68. The optical glass exhibits a low incipient deformation point and has good chemical durability.
|
