A deposition system for depositing a chemical vapor onto a workpiece is disclosed, including a deposition chamber having a plurality of components for performing chemical vapor deposition on the workpiece. The workpiece is held by a lathe that rotates the workpiece relative to chemical burners that deposit silica soot on the workpiece. The deposition system has a gas panel for regulating the flow of gases and vapors into the deposition chamber, and a computer for controlling operation of the gas panel and the components in the deposition chamber. Multiple sets of chemical burners are disposed longitudinally along the length of the workpiece. Each set of burners is separated from other sets, such that each set of burners deposit silica particles onto generally different portions of a workpiece. The respective portions include an overlap segment in which one or more burners from one burner set will deposit silica particles on the same portion of the workpiece as one or more burners from another set.

A gas branching apparatus that branches and supplies a gas to first to N-th supply targets, includes first to N-th pipes wherein the first to N-th pipes are each branched into first to N-th branch pipes on a downstream end side, and wherein the i-th branch pipes of the respective first to N-th pipes are connected in common to the i-th supply target, and the i-th branch pipes of the respective first to N-th pipes are provided with valves, respectively, where i denotes each of integers of 1 to N.

A manufacturing apparatus for an optical fiber porous preform includes a reaction chamber configured to accommodate a starting material; at least one main burner provided in the reaction chamber, the at least one main burner being configured to be supplied with a gas containing at least a source gas and a flammable gas, such that particulates are to be generated from reaction of the source gas and the flammable gas and deposited on the starting material; at least one auxiliary burner configured to be directed toward an end portion of the starting material on which the particulates are to be deposited; and an airflow guide provided such that at least part of the airflow guide is located across the at least one auxiliary burner from the starting material.

In order to improve the yield of an optical fiber base material, provided is a manufacturing apparatus for manufacturing an optical fiber base material by forming a soot deposition body on a surface of a target rod, including a main burner that generates glass microparticles to be deposited on the target rod while moving in a longitudinal direction of the target rod; a pair of side burners that are arranged outside a movement range of the main burner and heat both ends of the soot deposition body formed on the surface of the target rod; and a shielding member that prevents the glass microparticles generated by the main burner from being deposited on the target rod farther outward than a segment of the target rod sandwiched by the pair of side burners.

A burner for synthesization to synthesize glass particles that form a porous glass base material is provided, the burner for synthesization including a raw material gas injection portion to inject raw material gas toward a target, a combustion assisting gas injection portion to inject combustion assisting gas in a direction in which the combustion assisting gas is merged with the raw material gas at a first merging point, and a combustible gas injection portion to inject combustible gas in a direction in which the combustible gas is merged with the combustion assisting gas at a second merging point that is positioned closer to the combustion assisting gas injection portion than the first merging point. In the above-described burner for synthesization, the combustion assisting gas injection portion may also include a plurality of injection ports arranged along one straight line.

A porous glass base material sintering method comprising measuring a feeding speed V.sub.f of a porous glass base material and a movement speed V.sub.w of a bottom end of the glass base material; performing a sintering treatment of the porous glass base material presetting, for each feeding distance L of the porous glass base material, a greater-than-1 target value .sub.S (L) of an elongation rate in a straight body portion of the porous glass base material calculated based on a ratio V.sub.w/V.sub.f, and controlling at least one of a temperature of the heating furnace and a feeding speed of the porous glass base material such that a measured value of the elongation rate of the porous glass base material matches with the target value .sub.S (L).

A deposition system for depositing a chemical vapor onto a workpiece is disclosed, including a deposition chamber having a plurality of components for performing chemical vapor deposition on the workpiece. The workpiece is held by a lathe that rotates the workpiece relative to chemical burners that deposit silica soot on the workpiece. The deposition system has a gas panel for regulating the flow of gases and vapors into the deposition chamber, and a computer for controlling operation of the gas panel and the components in the deposition chamber. Multiple sets of chemical burners are disposed longitudinally along the length of the workpiece. Each set of burners is separated from other sets, such that each set of burners deposit silica particles onto generally different portions of a workpiece. The respective portions include an overlap segment in which one or more burners from one burner set will deposit silica particles on the same portion of the workpiece as one or more burners from another set.

A deposition system for depositing a chemical vapor onto a workpiece is disclosed, including a deposition chamber having a plurality of components for performing chemical vapor deposition on the workpiece. The workpiece is held by a lathe that rotates the workpiece relative to chemical burners that deposit silica soot on the workpiece. The deposition system has a gas panel for regulating the flow of gases and vapors into the deposition chamber, and a computer for controlling operation of the gas panel and the components in the deposition chamber. Multiple sets of chemical burners are disposed longitudinally along the length of the workpiece. Each set of burners is separated from other sets, such that each set of burners deposit silica particles onto generally different portions of a workpiece. The respective portions include an overlap segment in which one or more burners from one burner set will deposit silica particles on the same portion of the workpiece as one or more burners from another set.

This burner for producing a fine glass particle deposited body is provided with a metallic gas-feed pipe that forms a burner body, and a cover for covering the gas-feed pipe, wherein: the gas-feed pipe and the cover are integrally formed; the gas-feed pipe has connected thereto a piping through which material gas, oxyhydrogen gas, and seal gas are supplied; and the cover covers, in the axial direction of the burner over a prescribed length and in a given constant outer diameter, the gas-feed pipe and a connection part of the piping connected to a lateral surface of the gas-feed pipe.

A burner for synthesization to synthesize glass particles that form a porous glass base material is provided, the burner for synthesization including a raw material gas injection portion to inject raw material gas toward a target, a combustion assisting gas injection portion to inject combustion assisting gas in a direction in which the combustion assisting gas is merged with the raw material gas at a first merging point, and a combustible gas injection portion to inject combustible gas in a direction in which the combustible gas is merged with the combustion assisting gas at a second merging point that is positioned closer to the combustion assisting gas injection portion than the first merging point. In the above-described burner for synthesization, the combustion assisting gas injection portion may also include a plurality of injection ports arranged along one straight line.