BURNER FOR DEPOSITION OF OPTICAL FIBER PREFORM

摘要

A burner for depositing optical fiber preforms is provided to secure high deposition efficiency in a whole deposition process even when a large material is produced. A burner for depositing optical fiber preforms has a port for jetting a combustible gas with a plurality of small caliber supporting gas jetting ports. The burner having a concentric multi pipe structure is located further than a glass source gas jetting port(6). Optical fiber preforms are manufactured by hydrolyzing the glass source gas to generate glass particles using the burner and depositing the generated glass particles on a starting member. If the focal distance of the small caliber supporting gas jetting ports is L1 and the distance from the end of the small caliber supporting gas jetting ports to a glass particle deposited surface(7) is L2, L1 is greater than L2 at early deposition stage and L1 becomes smaller than L2 during deposition.