| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide high refractive index optical glass having both of low temperature softening property suitable for precision press forming and superior glass stability suitable for the hot forming of a preform. <P>SOLUTION: The optical glass is characterized by containing, by mass, 13-30% B<SB>2</SB>O<SB>3</SB>, 0.1-4% Li<SB>2</SB>O, 17-35% ZnO, 15-45% La<SB>2</SB>O<SB>3</SB>, 4-15% (except 15%) Ta<SB>2</SB>O<SB>5</SB>, 0-10% ZrO<SB>2</SB>, 0-10% Nb<SB>2</SB>O<SB>5</SB>(wherein, Ta<SB>2</SB>O<SB>5</SB>/(Ta<SB>2</SB>O<SB>5</SB>+ZrO<SB>2</SB>+Nb<SB>2</SB>O<SB>5</SB>)>0.3), 0-20% WO<SB>3</SB>and 0-1% Sb<SB>2</SB>O<SB>3</SB>, having a refractive index (n<SB>d</SB>) of 1.80-1.84 and having an Abbe number (ν<SB>d</SB>) of 40.0-45.0. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
