Patent ID: 11952311

Abstract:
Disclosed are optical glass, a glass preform or an optical element made therefrom the same and an optical instrument. The optical glass is calculated by a mass percentage content relative to a total mass of glass converted by an oxide, and the optical glass includes: B2O3: 5˜25%, SiO2: 0.5˜15%, ZrO2: 1˜15%, TiO2: 0˜10%, Ta2O5: 0.5˜10%, and La2O3, Gd2O3, Y2O3 and Yb2O3 of which the sum is 50˜75%, and Nb2O5 is not contained, a weight ratio of La2O3 to Gd2O3, i.e., La2O3/Gd2O3, is 1.28˜1.625.