PRODUCTION OF POROUS BASE MATERIAL FOR OPTICAL FIBER

摘要

PURPOSE:To provide a porous base material for optical fibers at a low cost without requiring addition of Ge to a core part, by blowing fine glass particles containing fluorine onto a flame of CO and O2 on the outer periphery along the longitudinal direction of the core part. CONSTITUTION:A synthetic quartz is used as a core part 3. A vapor phase raw material 6 and fluorine gas 7 are fed to the central tube of a mutitubular burner 4, and CO 10 is fed to the second outer tube. Ar 8 is fed to the third outer tube, and O2 9 is fed to the outermost tube. Fine glass particles 11 and a flame of the CO 10 and O2 9 are blown on the outer periphery of the core part 3 to give the aimed porous base material.