An optical fiber with low attenuation is provided. The fiber is produced under conditions that reduce fictive temperature. Processing includes maintaining the fiber at temperatures at or near the glass transition temperature (T.sub.g) for an extended period of time. For silica-based fibers, the preferred temperatures are temperatures between 1000 C. and 1700 C. The extended residence times are achieved in a continuous fiber manufacturing process by increasing the path length of the fiber through a processing region maintained at temperatures between 1000 C. and 1700 C. The increased path length is achieved by including one or more fluid bearing devices in the processing region. The extended residence time in the processing region allows the structure of the glass fiber to relax more completely and to more closely approach the equilibrium state. The more relaxed glass structure leads to a lower fictive temperature and provides fibers with lower attenuation.

The present invention, as disclosed and described herein, in one aspect thereof comprises a preform for making a vortex optical fiber includes a glass cylinder formed substantially of silicone dioxide that defines a core portion along a longitudinal axis of the glass cylinder and a cladding portion surrounding the core portion. The glass cylinder further defines a plurality of holes running parallel to the longitudinal axis from a first end of the glass cylinder to a second end of the glass cylinder.

A method of producing an optical fiber is provided that includes the steps of flowing a first gas into an optical fiber draw furnace. The first gas is passed through a heated section configured to contain and heat a glass source from which the optical fiber is drawn, passing the first gas through a muffle which defines a capture chamber. A portion of the first gas is removed through at least one reclaim port operatively coupled to the capture chamber. A second gas flows into a gas screen at a rate configured to substantially recover a pressure drop associated with removing the portion of the first gas.

A preform for making a vortex optical fiber comprises a glass cylinder formed substantially of silicone dioxide that defines a core portion along a longitudinal axis of the glass cylinder and a cladding portion surrounding the core portion. The glass cylinder further defines a plurality of holes running parallel to the longitudinal axis from a first end of the glass cylinder to a second end of the glass cylinder.

An optical fiber comprises, from a center to a periphery, a fiber core of undoped silica; a cladding layer; and a coating of polyacrylate, wherein the fiber core has a radius of 5 to 7 m and an ellipticity of less than 1.5%, the cladding layer with an ellipticity of less than 0.4% comprises inner, intermediate, and outer cladding layers, the inner cladding layer being doped with fluorine of 5 to 12 m thickness, and refractive index difference to fiber core of 0.4 to 0.2%, the outer cladding layer being undoped quartz of 25 to 45 m thickness, and the coating comprises an inner coating of 25 to 40 m thickness, and an outer coating of 25 to 35 m thickness and an ellipticity of less than 2%. The optical fiber has high durability and large effective transmission area, a method and system for preparing such optical fiber are also disclosed.

A fluid bearing for directing optical fibers during manufacturing is presented. The fluid bearing provides a flow of fluid to levitate and direct an optical fiber along a process pathway. The optical fiber is situated in a fiber slot and subjected to an upward force from fluid flowing from an inner radial position of the fiber slot past the optical fiber to an outer radial position of the fiber slot. The levitating force of fluid acting on the optical fiber is described by a convex force curve, according to which the upward levitating force on the optical fiber increases as the optical fiber moves deeper in the slot. Better stability in the positioning of the optical fiber in the fiber slot is achieved and contact of the optical fiber with solid surfaces of the fluid bearing is avoided. Various fluid bearing structures for achieving a convex force curve are described.

A method for making an optical fiber device may include using a three-dimensional (3D) printer to generate a preform body including an optical material. The preform body may have a 3D pattern of voids therein defining a 3D lattice. The method may further include drawing the preform body to form the optical fiber device.

The core region of an optical fiber is doped with chlorine in a concentration that allows for the viscosity of the core region to be lowered, approaching the viscosity of the surrounding cladding. An annular interface region is disposed between the core and cladding and contains a concentration of fluorine dopant sufficient to match the viscosity of the core. By including this annular stress accommodation region, the cladding layer can be formed to include the relatively high concentration of fluorine required to provide the desired degree of optical signal confinement (i.e., forming a low loss optical fiber). The inclusion of the annular stress accommodation region allows for the formation of a large effective area optical fiber that exhibits low loss (i.e., <0.19 dB/km) in both the C-band and L-band transmission ranges.

Provided is an optical fiber containing an alkali metal element or the like having a smaller diffusion coefficient than K and having a low Rayleigh scattering loss. An optical fiber is composed of silica glass and includes a core and a cladding arranged to surround the core which has a lower refractive index than the core. The core includes a first core including a central axis and a second core arranged to surround the first core. The average concentration of an alkali metal element or alkaline-earth metal element in the first core is 10 mol ppm or less. The average concentration of chlorine in the first core is 2000 mol ppm or more. The average concentration of an alkali metal element or alkaline-earth metal element in the second core is 10 mol ppm or more. The average concentration of chlorine in the second core is 10 to 600 mol ppm.

A method of manufacturing an optical fiber wire includes applying ultraviolet curable resin onto the outer periphery of a traveling optical fiber, cooling the ultraviolet curable resin applied to the optical fiber using first cooled inert gas, and curing the ultraviolet curable resin by radiating ultraviolet rays on the ultraviolet curable resin that is cooled by the first cooled inert gas through an ultraviolet transparent tube.