| 摘要 |
PURPOSE:To produce a quartz base material for an optical fiber doped with a substantial amt. of fluorine in glass for clad by forming a porous glass layer cosisting of boron oxide-contg. quartz on the outside of a bar-spaped base material consisting of quartz glass then sintering the same in an atmosphere contg. a fluorinating agent. CONSTITUTION:(i) A porous glass layer 2 of high-purity quartz glass incorporated therein with about 5mol% boron oxide is formed on the surface of a porous bar- shaped base material (may be a non-porous bar-shaped base material) 1 consisting of high-purity quartz glass. (ii) The bar-shaped base material mentioned above is sintered at about 1,100-1,500 deg.C in an atmosphere of an inert gas (e.g.; helium) incorporated threin with a fluorinating agent (e.g.; SF6, CF4, C2F4, CCl2F2), by which the quartz base material for an optical fiber incorporated with about 0.1-25mol% fluorine in the glass layer 2 is produced. |
