MANUFACTURE OF PREFORM FOR OPTICAL FIBER

摘要

PURPOSE:To obtain a preform which is uniform in the axial direction by attaching a windbreak for preventing a combustion flame from wavering to the tip of a burner for manufacturing a preform by a VAD method. CONSTITUTION:Various gases 2 such as starting materials for glass are fed to a burner 1, and fine glass particles 4 formed in a tightly sealed reactor 3 are deposited on a starting member 5 while rotating and pulling up the member to obtain a preform 6 for an optical fiber. At this time, part of the particles 4 become excess fine particles, and most of them are removed from an exhaust port 7. By attaching a windbreak 8 made of quartz to the burner 1, the flame is made independent of evacuation and external turbulence such as gaseous convection in the reactor 3, and the waver of the flame is reduced to a negligible degree.