| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an aspheric lens made of a high refractive index low dispersion glass to constitute a compact and highly functional imaging optical system. <P>SOLUTION: The aspheric lens produced by precision press forming of an optical glass comprises an optical glass having a refractive index (n<SB>d</SB>) of over 1.83, Abbe's number (ν<SB>d</SB>) of 40 or more and containing, in terms of mol%, 20 to 45% of B<SB>2</SB>O<SB>3</SB>, 5 to 24% of La<SB>2</SB>O<SB>3</SB>, 22 to 42% of ZnO and no Li<SB>2</SB>O, and has an optical thin film on the surface. <P>COPYRIGHT: (C)2007,JPO&INPIT |
