Fabrication of low-loss optical fibers by hybridized process

A hybridized process for the fabrication of low-loss single-mode optical fibers has been studied. Single-mode optical fibers with losses of 0.336 dB/km at 1.3 mu m and 0.205 dB/km at 1.55 mu m are fabricated from commercial silica powder having an average particle diameter of 10 mu m and a VAD-derived core rod having a core/cladding diameter ratio of 1/3, by a hybridized process by which the core rod is directly overcladded with a porous body formed from the silica powder by means of the cold isostatic pressing (CIP) technique. Further, polymer-clad silica-core optical fibers with a loss of 7.5 dB/km at 0.85 mu m are also fabricated using silica glass prepared from the silica powder by the same CIP hybridized process. (C) 1997 Scripta Technica, Inc.