A system for positioning an optical preform in a furnace is provided that includes an upper muffle and a downfeed handle assembly with a tube defining a first end and a second end, the second end extending into the upper muffle. A handle is disposed within the tube. A second end of the handle extends into the upper muffle and a seal assembly is positioned around both the tube and the handle. The first end of the handle extends through the seal assembly and a drive assembly is coupled with the downfeed handle.

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.

In the process comprising manufacturing a glass fine particle deposit (soot) by injecting glass fine particles generated with a burner for glass fine particle synthesis to a starting material rotating around its central axis as an axis of rotation; and sintering the glass fine particle deposit to vitrify it into transparent glass by suspending and heating the glass fine particle deposit in a furnace core tube, it is characterized that a product of a time period (min) during which a part of the glass fine particle deposit is heated in a heating zone in the furnace core tube and a linear speed (m/min) of sintering gas flowing in the furnace core tube is 15.5 (m) or more.

According to a fabrication method for fabricating a porous glass base material for optical fiber, the orientation of a clad forming burner used to form the outermost layer of a clad-corresponding portion is changed further upward while glass fine particles are deposited during the period between a first timing and a second timing. At the first timing, the outer diameter of the porous glass base material for optical fiber has not reached a target outer diameter. The second timing is later than the first timing, and either a timing at which the outer diameter of the porous glass base material for optical fiber reaches the target outer diameter for the first time, or a timing prior to this timing.

A horizontal lathe for manufacturing a porous optical fiber preform, the horizontal lathe being configured to hold and fix two opposite ends of a target in such a manner that a longitudinal direction of the target is a substantially horizontal direction, and cause the target to be rotated around an axis parallel to the longitudinal direction thereof as a rotation axis. The horizontal lathe includes a thermal expansion absorbing mechanism configured to absorb a change in dimension of the target, the change being due to thermal expansion of the target in a direction of the rotation axis.

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.

An optical fibre preform suspending device for vertically holding an optical fibre preform by a preform handle comprising a handle enlarged-width portion is provided. The preform suspending device having a substantially cylindrical shape and comprising a housing portion having a receiving space with a front top opening and a front bottom opening and a supporting surface between the front top opening and the front bottom opening. The preform suspending device also comprises a supporting member placed on the supporting surface, for holding the handle enlarged-width portion. The supporting member is radially independent from the housing portion.

A method for forming an optical fiber preform is provided. The method includes inserting a glass core cane into a glass sleeve such that the glass sleeve surrounds a portion of the glass core cane and such that there is a gap between the glass sleeve and the portion of the glass core cane surrounded by the glass sleeve. The method further includes depositing silica soot onto at least a portion of the glass core cane and at least a portion of the glass sleeve to form a silica soot preform, and flowing gas through the gap during processing of the silica soot preform.

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.