| 摘要 |
<p>An optical glass which has a refractive index of 1.46 to 1.58 and an Abbe value (nud) of 65 to 74, wherein it comprises, in molar %, 45 to 65 % of P2O5, 8 to 19 % of Al2O3, 5 to 30 % of MgO, 1 to 25 % of the total amount of Li2O, Na2O and K2O, 0 to 16 % of B2O3, 0 to 25 % of ZnO, 0 to 25 % of CaO, 0 to 25 % of SrO, 0 to 30 % of BaO, 0 to 10 % of La2O3, 0 to 10 % of Gd2O3, 0 to 10 % of Y2O3, 0 to 10 % of Yb2O3 and 0 to 10 % of Lu2O3, with the proviso that the sum of the contents of the above components is 95 % or more, and exhibits a specific weatherability index.</p> |
