Patent ID: 7232779

Claim:
Optical glass comprising, in a molar percent, 30 to 45 percent of B 2 O 3 , 2 to 15 percent of SiO 2 , 10 to 20 percent of La 2 O 3 , 1 to 10 percent of TiO 2 , 10 to 30 percent of ZnO, 2 to 15 percent of Li 2 O, higher than 0 percent and 10 percent or less of WO 3 , 0 to 15 percent of Nb 2 O 5 , and 0 to 10 percent of ZrO 2 , wherein the total amount of the B 2 O 3 , SiO 2 , La 2 O 3 , TiO 2 , ZnO, Li 2 O, WO 3 , Nb 2 O 5 and ZrO 2 is higher than 95 percent, and the glass exhibits a refractive index (nd) in a range of 1.75 to 1.87 and an Abbé number (νd) in a range of 30 to 45 wherein the glass contains no Ta 2 O 5 .