Patent ID: 8852745

Claim:
An optical glass, which comprises, denoted as weight percent, 2 to 37 percent of SiO 2 , 0 to 25 percent of B 2 O 3 , 0 to 10 percent of GeO 2 , 18 to 55 percent of a combined content of Li 2 O, Na 2 O, K 2 O, CaO, SrO, and BaO, 33.78 to 55 percent of a combined content of TiO 2 , Nb 2 O 5 , and WO 3 , and 0 to 15 percent of La 2 O 3 ; wherein the weight ratio of SiO 2 content relative to a combined content of SiO 2 and B 2 O 3 (SiO 2 /(SiO 2 +B 2 O 3 ) ranges from 0.1 to 1; a weight ratio of the Li 2 O content to a combined content of Li 2 O, Na 2 O, K 2 O, CaO, SrO, and BaO (Li 2 O/(Li 2 O+Na 2 O+K 2 O+CaO+SrO+BaO) ranges from 0 to 0.4; and a weight ratio of TiO 2 content relative to a combined content of TiO 2 , Nb 2 O 5 , and WO 3 (TiO 2 /(TiO 2 +Nb 2 O 5 +WO 3 ) ranges from 0.35 to 1; a specific gravity being equal to or less than 4.3; and which has a refractive index nd ranging from 1.87939 to 1.990 and an Abbé number νd ranging from 21 to 29.