| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an optical glass which has a high refractive index and a high transmissivity in the ultraviolet region. <P>SOLUTION: The invention relates to the optical glass containing Si, Al, Ca and O. The optical glass contains Si in an amount of 7% or more and 93% or less, in cation percent, Al in an amount of 2% or more and 57% or less, in cation percent, and Ca in an amount of 2% or more and 52% or less, in cation percent. In the optical glass, the total amount of Si, Al and Ca is 99.5% or more, in cation percent. Further, the optical glass contains Fe and Na each in an amount of 0.01 wt.ppm or less and has a transmissivity to a light having a wavelength of 248 nm of 16.9% or more at a thickness of 5 mm. <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
