Materials and processes for fiber preform fabrication—Vapor-phase axial deposition

The vapor-phase axial deposition (VAD) process was developed to realize continuous fabrication of high-silica fiber preforms. This process could be used to fabricate various kinds of optical fibers such as graded-index, single-mode, and high NA fibers. Transmission characteristics of these VAD fibers have improved to the level almost comparable to the best values attained by the MCVD process. The VAD process has excellent prospects as an economical means to produce long-length fibers with good transmission characteristics.