Patent attributes
An optical glass includes, in percent by weight, 2-11% SiO2, 28-45% B2O3, 2-15% CaO, 3-18% ZnO, 1-8% ZrO2, 9-40% La2O3, 0.5-11% Gd2O3, 0-10% Y2O3, 0-3% Al2O3, at most 8% R2O, where R2O is selected from the group consisting of Li2O, Na2O and K2O, at most 20% R′O, where R′O is selected from the group consisting of MgO, CaO, SrO and BaO, 0-3% WO3, 0-2% Nb2O5, and 0-1% Sb2O3. The optical glass is free from environmental and human harmful components such as PbO and As2O3. The optical glass has a refractive index in the range of 1.66-1.72, an Abbe number in the range of 51-56, a liquidus temperature (LT) of at most 1000° C. and a raw material melting temperature of at most 1300° C. The optical glass is suitable for mass production, and is stable against devitrification during manufacturing of preforms and precision molding of lenses.
