A lathe system for producing an optical fiber preform, the lathe system including a rotating bait rod, a burner box configured to deposit silica-containing soot on the rotating bait rod, a hood configured to direct airflow within the lathe system through an exhaust, and a perforated floor configured to expel air within the lathe system as a plurality of air jets from a bottom portion of the lathe system to a top portion of the lathe system.

A manufacturing method for an optical fiber preform includes forming a porous material made of fine silica glass particles surrounding a plurality of glass rods; and sintering the porous material, wherein the forming the porous material includes forming the porous material such that two or more of the plurality of glass rods protrude from the porous material, and the sintering includes supporting end portions of protruding sides of the two or more protruding glass rods collectively with a support jig, and performing the sintering. With this, a reduction in manufacturing yield is suppressed.

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 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.

To prevent a lowering of gripping force due to temperature changes, provided is a gripping mechanism including a plurality of chuck claws that, when having come close to each other, generate a gripping force on a gripped body; a chuck body that holds the plurality of chuck claws on a common planar surface, and moves them on the planar surface; and a plurality of chuck plates that, when each of the plurality of chuck claws grips the gripped body, are interposed between each of the plurality of chuck claws and the gripped body. A thermal expansion coefficient .sub.1 of the plurality of chuck claws, a thermal expansion coefficient .sub.2 of the plurality of chuck plates and a thermal expansion coefficient .sub.W of the gripped body have a relationship indicated by
.sub.W<.sub.1<.sub.2(Equation 1).

Monolithic optical structures include a plurality of layer with each layer having an isolated optical pathway confined within a portion of the layer. The monolithic optical structure can be used as an optical fiber preform. Alternatively or additionally, the monolithic optical structure can include integrated optical circuits within one or more layers of the structure. Monolithic optical structures can be formed by performing multiple passes of a substrate through a flowing particle stream. The deposited particles form an optical material following consolidation. Flexible optical fibers include a plurality of independent light channels extending along the length of the optical fiber. The fibers can be pulled from an appropriate preform.

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 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 production method of an optical fiber preform includes first preparing a first preform having a plurality of glass preforms and a first cladding portion disposed between the plurality of glass preforms, and first arranging a second cladding portion to surround the first preform. At the first arranging, a material gas and a combustion gas are ejected from a burner to produce glass particles. The first preform and the burner are moved relative to each other in a longitudinal direction of the first preform. The glass particles are deposited on the first preform.

A known method for producing a tubular quartz glass composite body in an outer deposition process comprises providing and rotating a substrate tube about an axis of rotation, depositing SiO.sub.2 particles on the outer jacket surface of the tube forming a composite consisting of the tube and a SiO.sub.2 soot body, and sintering the composite by heating to form the tubular quartz glass composite body, and using a holding device which is suitable for holding the composite body at least temporarily in the heating zone with the longitudinal axis of the substrate tube oriented vertically. To enable the production on this basis of a tubular composite body consisting of quartz glass with a particularly large inner diameter and with a wall with reduced scrap, it is proposed that a holding device is used which comprises a holding element which is produced in a holding region of the substrate tube.