HIGH-REFRACTIVITY LOW-DISPERSION OPTICAL GLASS

摘要

An optical glass having high refractivity, low dispersion and high transmittance. The glass comprises 6-17 wt% of B2O3, 2-10 wt% of SiO2, greater than 25 wt% and less than 45 wt% of La2O3, 5-25 wt% of Gd2O3, 0-3 wt% of Nb2O5, greater than 19 wt% and less than 27 wt% of Ta2O5, 0-16 wt% of ZnO, 0-5 wt% of BaO, 0-5 wt% of CaO, 0-5 wt% of SrO, 0-9 wt% of ZrO2, 0-8 wt% of Y2O3, 0-8 wt% of Yb2O3, 0-5 wt% of WO3, 0-2 wt% of Li2O+Na2O+K2O, greater than or equal to 0.01 wt% and less than 0.1 wt% of Sb2O3 and 0-1 wt% of SnO2. The glass has a refractive index of 1.85-1.90, an Abbe number of 35-45 and a wavelength of not more than 440nm when transmittance is up to 80%.