| 摘要 |
A torch (24) used in the Vapor-phase Axial Deposition (VAD) process to form small diameter cores for single mode lightguide preforms. The torch (24) is comprised of a plurality of concentrically mounted, spaced, glass tubes (62, 63, 64, 65, 66) through which reactants and combustible materials are passed. A tapered shroud (68) is mounted about the end of the torch (24) and a shield gas directed along the inner surface thereof to confine and direct the gases and reactants to the surface of the soot form (12). |
