| 摘要 |
This invention is concerned with the production of glasses suitable for ophthalmic applications having refractive indices of 1.523+/-0.004, Abbe number between 51-59, densities less than 2.43 g/cm3, transmissions at 400 nm in 2 mm thickness greater than 89%, and a UV cutoff between 310-335 nm, said glasses consisting essentially, in weight percent on the oxide basis, of: - SiO2 49-71 Li2O + Na2O + K2O 8-20 - B2O3 5-26 TiO2 1.8-6 - Al2O3 0-14 ZrO2 0-5.5 - Li2O 0-4 As2O3 and/or Sb2O3 0-0.7 - Na2O 0-16 Cl and/or Br 0-1 - K2O 0-20 CaO and/or MgO 0-4 - and/or ZnO and/or BaO - |
