| 摘要 |
PURPOSE:To obtain the title glass form with excellent optical and NA characteristics, highly resistant to environmental deterioration, by imparting a quartz-based glass form produced by gelation and sintering of a silica sol solution with a concentration distribution of a fluorine component. CONSTITUTION:Firstly, an alkoxysilane (e.g., tetraethoxysilane), ethanol and water are mutually mixed to prepare a silica sol solution. Second, this solution is gelled to form a gel, which is then immersed in a sol solution of the alkoxysilane containing a fluorine component [FSi(OC2H5)4] to form a concentration distribution of said component from the surface of the gel to its interior. Thence, the resultant gel is dried and sintered into a transparent glass form, thus obtaining the objective quartz-based glass form with refractive index distribution, which can be suitably used for e.g., rod lenses. |
