Patent ID: 7217672

Claim:
An optical glass consisting of, in mass %, SiO 2 55.35–70% B 2 O 3 3–less than 15% PbO 0–2% Al 2 O 3 0–2.3% Li 2 O 0–3% CaO 0–2% SrO 0–2% ZrO 2 0–2% wherein the total amount of the CaO, SrO and Zr 2 ingredients is 2% or less and Na 2 O+K 2 O+BaO+ZnO in the total amount of 10–45% TiO 2 0–0.5% and fluoride or fluorides substituting for the above oxide or oxides partially or entirely, a total amount of F contained in the fluoride or fluorides being 8.4–11%, said optical glass including a fluorine ingredient and/or a titanium oxide ingredient and/or an arsenic oxide ingredient.