| 摘要 |
PURPOSE:To reduce an amount of fluorine gas used and to obtain low-cost optical fiber of total fluorine dope by dehydrating a porous material for optical fiber, doping the porous material with fluorine and heating in an atmosphere containing chlorine and an inert gas. CONSTITUTION:A porous material for optical fiber comprising fine particles of quartz glass as a main component is heated and dehydrated in an atmosphere containing at least chlorine and an inert gas at a temperature completely not to make the porous material for optical fiber into glass. Then the porous material is exposed to the atmosphere containing chlorine and the inert gas at a temperature lower than the dehydration temperature and fluorine is doped into the porous material for optical fiber. Then the porous material is heated in the atmosphere containing chlorine and the inert gas and made into transparent glass to give the aimed perform for optical fiber. By this method, since an amount of expensive fluorine used can be reduced, low-cost optical fiber of total fluorine dope is obtained. |
