| 摘要 |
PROBLEM TO BE SOLVED: To provide an optical glass for a mold press molding capable of satisfying all of the following requirements of (1) which does not contain a lead component, an arsenic component and an F component which are not desirable environmentally, (2) which has a glass transition temperature of ≤650°C, (3) which has a high refractive index and which is low in dispersion and (4) which has an excellent devitrification resistance at the time of preforming molding. SOLUTION: The optical glass for the mold press molding contains by mass% 3-21% SiO<SB>2</SB>, 6.5-30% B<SB>2</SB>O<SB>3</SB>, 6-40% ZnO, 2-10% ZrO<SB>2</SB>, 20-46% La<SB>2</SB>O<SB>3</SB>, 0-16% Gd<SB>2</SB>O<SB>3</SB>and less than 0-1% Nb<SB>2</SB>O<SB>5</SB>and does not contain the lead component, the arsenic component and the F component. COPYRIGHT: (C)2009,JPO&INPIT |
