PRODUCTION OF PREFORM FOR OPTICAL FIBER

摘要

PURPOSE:To efficiently and stably obtain a large-sized glass particulate deposit by depositing glass particulates on the outer peripheral part of a starting material by a vapor phase method to form a composite, then freshly depositing the glass particulates on the outer peripheral part of this composite. CONSTITUTION:Glass raw materials are supplied within flames 3-1 of a burner 2-1 for synthesizing the glass particulates to form the glass particulates. The formed glass particulates are begun to be deposited on the outer peripheral part of the columnar or cylindrical starting material 1 rotating around its own axis as the axis of rotation from near one end of the starting material 1. This burner 2-1 for synthesizing the glass particulates are successively moved relatively in parallel with the axis of the starting material 1, by which the glass particulate deposit 1-4 is formed in the outer peripheral part of the starting material 1 and the composite 8 is formed. The glass particulate are then freshly deposited on the outer peripheral part of the composite 8 by using a burner 2-2 for synthesizing the glass particulates, by which the preform for the optical fiber is produced.