Patent ID: 7906445

Claim:
An optical glass comprising, based on a total weight of the optical glass: 12 to 30 weight percent of P 2 O 5 ; 1 to 5 weight percent of B 2 O 3 ; 1 to 8 weight percent of Li 2 O; 0.5 to 10 weight percent of Na 2 O; 0.5 to 15 weight percent of K 2 O; 1 to 5 weight percent of CaO; 0 to 20 weight percent of BaO; 0 to 5 weight percent of SrO; 1 to 10 weight percent of TiO 2 ; 1 to 20 weight percent of Bi 2 O 3 ; 5.0 to 32 weight percent of Nb 2 O 5 ; 13 to 60 weight percent of WO 3 ; and 0 to 1 weight percent of Sb 2 O 3 , wherein a total weight of Na 2 O and K 2 O is in a range of 3 to 20 weight percent based on the total weight of the optical glass and wherein said optical glass has: a refractive index (nd) in a range of 1.80 to 1.85, an Abbe number (vd) in a range of 20 to 28.5, a glass transition temperature (Tg) not higher than 520° C., and a liquid phase temperature (TL) not higher than 700° C.