| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an optical glass having a small partial dispersion ratio (θg, F), while a refractive index and an Abbe number are in each desired range, capable of suppressing deterioration with time of a spectral transmittance, and to provide a preform and an optical element using the optical glass. <P>SOLUTION: This optical glass contains in mol%, a 10.0-60.0% SiO<SB POS="POST">2</SB>component and a >0% Ta<SB POS="POST">2</SB>O<SB POS="POST">5</SB>component with respect to the glass whole material amount having a composition in terms of oxides, and solarization (a deterioration amount of the spectral transmittance at the wavelength of 450 nm) is ≤5.0%. <P>COPYRIGHT: (C)2013,JPO&INPIT |
