A method of manufacturing at least one optical fibre preform comprising: providing a plurality of partially porous intermediate preforms, each partially porous intermediate preform having a longitudinal axis and comprising a respective soot intermediate clad layer formed around a respective glass core rod comprising a central core region of radius a and an inner clad region of radius b to define a first core-to-clad ratio a/b; consolidating the formed soot intermediate clad layers to form a respective plurality of intermediate glass preforms, each of the plurality of intermediate glass preforms comprising an intermediate clad region having an external radius c to define a second core-to-clad ratio a/c of from 0.20 to 0.30 , and overcladding at least one intermediate glass preform by forming an overclad region surrounding the intermediate clad region to form an optical fibre glass preform, wherein consolidating comprises exposing the plurality of intermediate preforms to a consolidation hot zone of a single furnace body while rotating each of the intermediate preforms about its respective longitudinal axis.

Provided is a glass base material hanging mechanism that, when hanging a starting member or a glass base material, can tightly (solidly) connect the hanging shaft tube and the hanging component and can vertically align the hanging component and the center of the glass base material.

A method for producing a depressed-cladding core rod of an ultra-low water peak optical fiber, the method including 1) producing a core rod component; 2) producing an inner cladding casing component; 3) disposing the core rod hollow shaft and the casing hollow shaft respectively in the glass lathe; 4) cutting off connections among a pressure controlling pipe, a scrubber, and a vacuum pump; 5) connecting the inner cladding casing to the core rod hollow shaft hermetically; 6) turning on the glass lathe; 7) transporting a first mixture gas to the core rod hollow shaft; 8) moving a high temperature heat source; 9) transporting a second mixture gas to the core rod hollow shaft; 10) transporting the first mixture gas to the core rod hollow shaft; 11) transporting the first mixture gas under certain conditions; and 12) controlling relevant parameters to fuse the inner cladding casing with the core layer rod.

The present invention intends to reduce unevenness on a surface of an optical fiber preform. The apparatus for manufacturing an optical fiber preform including a support portion rotating a core rod at a rotation speed r around a rotation axis of the core rod extending in a longitudinal direction of the core rod and at least one burner array including N sets (N is an integer of 2 or more) of burners provided at intervals of a distance d and a material ejection port, and moving around the core rod at a speed v in the longitudinal direction to form a porous glass portion on an outer periphery of the core rod. A rotation number (L+x) of the core rod when the burner array moves the distance d in the longitudinal direction is represented by rd/v=L+x where the L is an arbitrary natural number and the offset x is greater than 0.5 and less than or equal to 0.5, an absolute value of the offset x is greater than 2/(2N+1) and less than 3/(3N1).

A method of forming a multicore fiber comprises the steps of drilling a plurality of holes in a soot blank, inserting a plurality of graphite rods into the plurality of holes to form a soot preform assembly, consolidating the soot preform assembly in a high temperature furnace to form a glass preform assembly, removing the plurality of graphite rods from the glass preform assembly to form a solid glass preform containing multiple holes, inserting a plurality of glass core canes into the holes to form a multicore preform, placing the multicore preform in a draw furnace, and drawing multicore fiber from the multicore preform.

A system and methods are described herein for preheating a preform in a preheater furnace and then transferring the preheated preform to a consolidation furnace for chemical treatment and sintering the preform into a clear glass which can be drawn into optical fiber. In addition, the preheater furnace is described herein which is configured to heat the preform per a predetermined heat-profile until the preform is uniformly heated to a temperature above 1000 C.

A method for manufacturing an optical fiber. The method includes a drawing step of drawing a glass base material while feeding the glass base material to a heating furnace, to manufacture an optical fiber. The glass base material includes a core rod and a cladding tube into which the core rod is inserted. A support tube is bonded to an upper end of the cladding tube, to communicate with a gap between the core rod and the cladding tube. The drawing step includes bringing the gap and an internal space of the support tube into a state of being lower in pressure than atmospheric pressure.

The present application provides a method for recovering and reusing quartz powder waste in an out-of-tube deposition process. The quartz powder recovered by this method meets the optical performance requirements for the preparation of an optical fiber preform rod having a functional cladding, reduces the production cost, and solves the problem of environmental pollution. Also, the present invention further provides a method for preparing an optical fiber preform rod by using the recovered quartz powder. The method reduces and simplifies the difficulty in the manufacturing of a core rod of a preform rod, and simplifies the difficulty in the manufacturing of some preform rods of special structures.

A method of processing glass filament comprises: providing a length of glass filament from which a portion is to be separated from the remainder of the filament; directing energy onto the filament in order to cause a decrease in a width of the filament at a desired location for separation of the portion; and causing relative longitudinal movement between the portion and the remainder of the filament to separate the portion from the remainder of the filament at the desired location.

A method of processing glass filament comprises: providing a length of glass filament from which a portion is to be separated from the remainder of the filament; directing energy onto the filament in order to cause a decrease in a width of the filament at a desired location for separation of the portion; and causing relative longitudinal movement between the portion and the remainder of the filament to separate the portion from the remainder of the filament at the desired location.