| 摘要 |
<p>Provided is an optical glass which has high refractive index (refractive index of 1.70 or higher) and low dispersion (Abbe number of 40 or higher) optical characteristics, a low deformation point (520ºC or lower), and good devitrification resistance during molding, and which is suitable for shaping molds such as press molding of precision molds. The optical glass includes B, Si, Li, R, Zn, La, and W in the following amounts in terms of oxide conversion: B2O3: between 20.0 and 35.0 wt%; SiO2: between 1.0 and 4.5 wt%; Li2O: greater than 2.5 wt% but equal to or less than 6.0 wt%; RO: between 5.0 and 15.0 wt% (where BaO: between 5.0 and 10.0 wt%); ZnO: between 18.0 and 30.0 wt%; La2O3: between 10.0 and 20.0 wt%; and WO3: between 2.0 and 12.0 wt%, where R is one or more elements selected from among Mg, Ca, Sr, and Ba.</p> |
