| 摘要 |
PROBLEM TO BE SOLVED: To provide optical glass having a high refractive index, a low dispersion, a low glass transition temperature, and a low temperature softening property of precision press molding. SOLUTION: This optical glass contains, by mol, 15 to 45% B<SB>2</SB>O<SB>3</SB>, 5 to 20% La<SB>2</SB>O<SB>3</SB>, 1 to 20% Gd<SB>2</SB>O<SB>3</SB>, 10 to 45% ZnO, 0 to 15% WO<SB>3</SB>, 0 to 10% Ta<SB>2</SB>O<SB>5</SB>, 0 to 10% Nb<SB>2</SB>O<SB>5</SB>, 0 to 20% TiO<SB>2</SB>, 0 to 20% SiO<SB>2</SB>, 0 to 15% Li<SB>2</SB>O, 0 to 10% Na<SB>2</SB>O, 0 to 10% K<SB>2</SB>O, 0 to 10% MgO, 0 to 10% CaO, 0 to 10% SrO, 0 to 10% BaO, 0 to 8% Y<SB>2</SB>O<SB>3</SB>, 0 to 8% Yb<SB>2</SB>O<SB>3</SB>(wherein, the total content of La<SB>2</SB>O<SB>3</SB>, Gd<SB>2</SB>O<SB>3</SB>, Y<SB>2</SB>O<SB>3</SB>and Yb<SB>2</SB>O<SB>3</SB>is 10 to 30%), 0 to <0.5% ZrO<SB>2</SB>, 0 to 10% Bi<SB>2</SB>O<SB>3</SB>and 0 to 1% Sb<SB>2</SB>O<SB>3</SB>, and has a refractive index (nd) of >1.86, an Abbe's number (νd) of 35 to <39.5 and a glass transition temperature (Tg) of≤630°C. COPYRIGHT: (C)2008,JPO&INPIT
|
