| 摘要 |
The invention provides phosphate optical glass having the refractive index of 1.57-1.62 and the abbe number of 65-70. The optical glass has a small coefficient of thermal expansion and is suitable for precision press forming. The phosphate optical glass comprises following components by mole: 32-50% of P2O5, 3-20% of B2O3, 12-25% of BaO, 0-20% of SrO, 0-8% of Al2O3, more than 0 and not more than 15% of Li2O, more than 0 and not more than 11% of MgO, 0-15% of CaO, 0-5% of Gd2O3, 0-5% of La2O3, and 0-0.5% of Sb2O3, and is free of ZnO. By reasonable distribution of the contents of the components, the coefficient of thermal expansion that is alpha of the optical glass is lower than 110*10<-7> /DEG C, and the transformation temperature is lower than 520 DEG C. |
