Optical glass

摘要

An optical glass consisting basically of a B2O3-La2O3 - ZrO2-Nb2O5-PbO-BaO (and/or ZnO) system is free from a poisonous CdO or ThO2 component and has an excellent light transmission property in a transition region from an ultraviolet portion to a visible portion as compared with conventional optical glasses having the same optical properties.