| 摘要 |
To provide an optical glass which has a high transmittance and a high refractive index and shows little decrease in the transmitted light intensity when continuously irradiated with a blue-violet laser diode light, and which is less prone to a higher melting temperature and exhibits chemical durability being not low. An optical glass consisting essentially of, as represented by mol %, from 35 to 54% of TeO<SUB>2</SUB>, from 0 to 10% of GeO<SUB>2</SUB>, from 5 to 30% of B<SUB>2</SUB>O<SUB>3</SUB>, from 0 to 15% of Ga<SUB>2</SUB>O<SUB>3</SUB>, from 0 to 8% of Bi<SUB>2</SUB>O<SUB>3</SUB>, from 3 to 20% of ZnO, from 0 to 10% of MgO+CaO+SrO+BaO, from 1 to 10% of Y<SUB>2</SUB>O<SUB>3</SUB>+La<SUB>2</SUB>O<SUB>3</SUB>+Gd<SUB>2</SUB>O<SUB>3</SUB>, from 0 to 5% of Ta<SUB>2</SUB>O<SUB>5</SUB>+Nb<SUB>2</SUB>O<SUB>5</SUB>, from 0 to 1.8% of TiO<SUB>2</SUB>, and from 0 to 6% of Li<SUB>2</SUB>O+Na<SUB>2</SUB>O+K<SUB>2</SUB>O+Rb<SUB>2</SUB>O+Cs<SUB>2</SUB>O. A lens made of such an optical glass.
|
