Patent ID: 7820576

Claim:
An optical glass for press-molding, comprising as glass ingredients, by weight: 0.5-4% SiO 2 ; 20-30% B 2 O 3 ; 10-20% ZnO; 1-10% ZrO 2 ; 30-45% La 2 O 3 ; 9-12% Nb 2 O 5 ; 1-15% WO 3 ; 0.5-3.5% TiO 2 ; 0.5-3% CaO; 0.1-0.5% Li 2 O; 0-0.4% Na 2 O (zero inclusive); and 0-0.4% K 2 O (zero inclusive), with a total content of Li 2 O+Na 2 O+K 2 O accounting for 0.1-0.5%.