The invention discribes a lead- and arsenic-free, preferably gadolinium-free and more preferably fluorin-free optical glass, having refractive index (nd) 1.19-2.05, Abbe number (vd) 19-25, low transition temperature of less than or equal to 470 DEG C, and preferably less than or equal to 450 DEG C, excellent productivity, excellent workability and excellent crystal stability, contains (by weight, on an oxide basis) more than 55% bismuth oxide (Bi2O3) and more than 13% germanium dioxide (GeO2) and has Bi2O3 to GeO2 ratio 5 or less. The inventive optical glass can be applied in mapping, projection, telecom, optical communication engineering, shifting drivers, laser technology and/or microlens array. |