LIGHTGUIDE PREFORM FABRICATION

摘要

LIGHTGUIDE PREFORM FABRICATION A lightguide preform is fabricated by depositing and consolidating a plurality of doped silica layers, containing volatile germania, on the inside surface of a silica glass tube. The tube is rotated while repeatedly traversing a hot zone therealong to shrink and collapse the tube in a final heat zone traversal. A gas mixture containing oxygen and germanium tetrachloride flow from an input gas line and through the tube during the shrinking traversals. The gas mixture continues to flow through at least a portion of the input gas line during the final heat zone traversal.