A method of manufacturing optical fiber in an optical fiber production system is provided. The method includes the providing a draw furnace operatively coupled to a slow cooling device along a draw pathway, drawing the optical fiber from an optical fiber preform in the draw furnace and along the draw pathway, heat treating the optical fiber in the slow cooling device positioned along the draw pathway, the slow cooling device comprising an inlet, an outlet, and a process tube extending between the inlet and the outlet, and selecting an opening size of an outlet nozzle operatively coupled to the outlet based on a draw speed of the optical fiber.

A method of processing an optical fiber that includes drawing an optical fiber along a fiber pathway through a hollow light pipe, wherein the hollow light pipe comprises a first end having an opening with a radius R.sub.p, a second end and a pipe body comprising a chamber extending from the first to the second end, the fiber pathway extending through the pipe body, and a reflective coating is disposed on the pipe body, and directing a light from a directed light source into the hollow light pipe through the opening such that the light is reflected by the reflective coating while propagating in the hollow light pipe, the optical fiber absorbing the light reflected by the reflective coating, wherein the light enters the opening of the hollow light pipe at an input angle in a range of from 10° to 70° with respect to the fiber pathway.

The invention discloses an apparatus (100) to fabricate U-bent fiber optic sensors, transducers and waveguides, using laser assisted technologies as heat source. The apparatus includes a heating source (110) and a robotic articulate arm (130) that may modify the geometry of an optical fiber (150) with either silica or polymer cladding and fabricate sensor probes by decladding the polymeric cladding in addition to twisting and bending of the optical fiber in an automated manner. The geometry of the optical fiber sensor probe is controlled by the heating source (110), beam (112) thickness, exposure time of fiber and the positioning of a motorized stage. The advantage of the apparatus includes reduction in fabrication time, repeatable and controllable bend diameter for any size of optic fiber probes.

The invention discloses an apparatus (100) to fabricate U-bent fiber optic sensors, transducers and waveguides, using laser assisted technologies as heat source. The apparatus includes a heating source (110) and a robotic articulate arm (130) that may modify the geometry of an optical fiber (150) with either silica or polymer cladding and fabricate sensor probes by decladding the polymeric cladding in addition to twisting and bending of the optical fiber in an automated manner. The geometry of the optical fiber sensor probe is controlled by the heating source (110), beam (112) thickness, exposure time of fiber and the positioning of a motorized stage. The advantage of the apparatus includes reduction in fabrication time, repeatable and controllable bend diameter for any size of optic fiber probes.

A method for monitoring optical fiber temperature includes heating an optical fiber using a heat source, and measuring an infrared radiation level emitted by an optical fiber during heating of the optical fiber. The method further includes comparing the infrared radiation level to a radiation level setpoint for the optical fiber to determine a radiation level error value. The method further includes adjusting a power level setpoint of the heat source based on the radiation level error value.

A method of making a multi-mode optical fiber that includes: depositing a porous germania-doped silica soot to form a germania-doped porous soot preform; depositing a porous silica layer over the porous soot preform; doping the porous soot preform and the porous silica layer with a fluorine dopant to form a co-doped soot preform having a core region and a fluorine-doped trench region; consolidating the co-doped soot preform to form a sintered glass, co-doped core preform having a refractive index alpha profile between 1.9 and 2.2 measured at 850 nm; depositing a cladding comprising silica over the sintered glass, co-doped preform to form a multi-mode optical fiber preform; drawing the optical fiber preform into a multi-mode optical fiber. Further, the step of doping the germania-doped soot preform and the porous silica layer is conducted according to a doping parameter (Φ) that is set between 20 and 300, and given by:

[00001]$\Phi =\frac{1\times {10}^{14}.Math.R_{\mathrm{prc}}^2.Math.\exp \left(-E/{\mathrm{RT}}_{\mathrm{dop}}\right).Math.T_{\mathrm{dop}}^{1/2}}{x^{3/4}}.$

A method of making a multi-mode optical fiber that includes: depositing a porous germania-doped silica soot to form a germania-doped porous soot preform; depositing a porous silica layer over the porous soot preform; doping the porous soot preform and the porous silica layer with a fluorine dopant to form a co-doped soot preform having a core region and a fluorine-doped trench region; consolidating the co-doped soot preform to form a sintered glass, co-doped core preform having a refractive index alpha profile between 1.9 and 2.2 measured at 850 nm; depositing a cladding comprising silica over the sintered glass, co-doped preform to form a multi-mode optical fiber preform; drawing the optical fiber preform into a multi-mode optical fiber. Further, the step of doping the germania-doped soot preform and the porous silica layer is conducted according to a doping parameter (Φ) that is set between 20 and 300, and given by:

[00001]$\Phi =\frac{1\times {10}^{14}.Math.R_{\mathrm{prc}}^2.Math.\exp \left(-E/{\mathrm{RT}}_{\mathrm{dop}}\right).Math.T_{\mathrm{dop}}^{1/2}}{x^{3/4}}.$

Methods of reshaping ferrules (20) used in optical fiber cables assemblies (170) are disclosed. The reshaping methods reduce a core-to-ferrule concentricity error (E), which improves coupling efficiency and optical transmission. The methods include measuring a distance (δ) and angular direction (θ) from a true center (30) of the ferrule to the core (46), wherein the true center (30) is based on an outer surface (26) of the ferrule. The methods also include reshaping at least a portion (26P) of the ferrule (20) to define a new true center (30′) of the ferrule (20) and reduce the distance (δ). A variety of reshaping techniques are also disclosed.

Methods of reshaping ferrules (20) used in optical fiber cables assemblies (170) are disclosed. The reshaping methods reduce a core-to-ferrule concentricity error (E), which improves coupling efficiency and optical transmission. The methods include measuring a distance (δ) and angular direction (θ) from a true center (30) of the ferrule to the core (46), wherein the true center (30) is based on an outer surface (26) of the ferrule. The methods also include reshaping at least a portion (26P) of the ferrule (20) to define a new true center (30′) of the ferrule (20) and reduce the distance (δ). A variety of reshaping techniques are also disclosed.

Known methods of producing a three-dimensional glass object comprise the step of shaping of a glass fiber, wherein the glass fiber provided with a protective sheath is fed continuously to a heating source, the protective sheath is removed under the influence of heat, and the glass fiber is softened. In order to facilitate the production of filigree or optically distortion-free and transparent glass objects as much as possible, and also enable the adjustment of optical and mechanical properties with high spatial resolution, in one aspect the glass fiber has a protective sheath with a layer thickness in the range of 10 nm to 10 μm.