An optical fiber includes a glass fiber, and a resin coating layer covering an outer circumference of the glass fiber. In a spectrum acquired by measuring an amount of eccentricity of the glass fiber from a central axis based on an outer circumference of the resin coating layer at a plurality of measurement points set at a predetermined interval in an axial direction of the glass fiber and applying Fourier transform of a waveform representing the amount of eccentricity at each of the plurality of measurement points, a largest value of amplitude of the amount of eccentricity is 6 μm or less.

An optical fiber includes a glass fiber, and a resin coating layer covering an outer circumference of the glass fiber. In a spectrum acquired by measuring an amount of eccentricity of the glass fiber from a central axis based on an outer circumference of the resin coating layer at a plurality of measurement points set at a predetermined interval in an axial direction of the glass fiber and applying Fourier transform of a waveform representing the amount of eccentricity at each of the plurality of measurement points, a largest value of amplitude of the amount of eccentricity is 6 μm or less.

The present disclosure provides coating compositions and cured products formed from the coating compositions. The cured products can be formed at high cure speeds from the coating compositions and feature low Young's modulus, high tear strength, and/or high tensile toughness. The cured products can be used as primary coatings for optical fibers. The primary coatings provide good microbending performance and are resistant to defect formation during fiber coating processing and handling operations. The coating compositions include an oligomer, an alkoxylated monofunctional acrylate monomer, and preferably, an N-vinyl amide compound.

The present disclosure provides coating compositions and cured products formed from the coating compositions. The cured products can be formed at high cure speeds from the coating compositions and feature low Young's modulus, high tear strength, and/or high tensile toughness. The cured products can be used as primary coatings for optical fibers. The primary coatings provide good microbending performance and are resistant to defect formation during fiber coating processing and handling operations. The coating compositions include an oligomer, an alkoxylated monofunctional acrylate monomer, and preferably, an N-vinyl amide compound.

Apparatus and method for producing elongated glass components with low bow. The apparatus may include a heating element to heat a bulk glass component where a strand may be drawn from the bulk glass component in a downward direction and a gripper device including a clamping element to support the strand while pulling or drawing it from the bulk glass component in a linear motion, and a low-friction mounting element attached to the clamping element which allows translational movement of the clamping element in an x-y plane. The gripper device may further be used to reduce bow in the strand while it is being drawn by moving the clamping element on the mounting element in a direction opposite the direction of any measured transverse acceleration.

Optical waveguide cores having refractive index profiles that vary angularly about a propagation axis of the core can provide single-mode operation with larger core diameters than conventional waveguides. In one representative embodiment, an optical waveguide comprises a core that extends along a propagation axis and has a refractive index profile that varies angularly about the propagation axis. The optical waveguide can also comprise a cladding disposed about the core and extending along the propagation axis. The refractive index profile of the core can vary angularly along a length of the propagation axis.

Methods for modifying multi-mode optical fiber manufacturing processes are disclosed. In one embodiment, a method for modifying a process for manufacturing multi-mode optical fiber includes measuring at least one characteristic of a multi-mode optical fiber. The at least one characteristic is a modal bandwidth or a differential mode delay at one or more wavelengths. The method further includes determining a measured peak wavelength of the multi-mode optical fiber based on the measured characteristic, determining a difference between the target peak wavelength and the measured peak wavelength, and modifying the process for manufacturing multi-mode optical fiber based on the difference between the target peak wavelength and the measured peak wavelength.

A method of manufacturing a multimode optical fiber includes specifying a peak wavelength λ.sub.P for the multimode optical fiber. The peak wavelength λ.sub.P corresponds to a wavelength at which the multimode optical fiber has a maximum bandwidth. The multimode optical fiber comprises a core and a cladding surrounding and directly adjacent to the core. The core has a radius r.sub.1 and a maximum relative refractive index Δ.sub.1,MAX>0. The cladding comprises a depressed-index region having a minimum relative refractive index Δ.sub.3,MIN<0 and a volume v. A draw tension T for the multimode optical fiber is selected based on a correlation relating peak wavelength λ.sub.P to draw tension T, the correlation comprising a correlation constant. The correlation constant K is a function of at least one of Δ.sub.1,MAX, r.sub.1, v, Δ.sub.3,MIN, and λ.sub.P. The multimode optical fiber is drawn from a preform at the draw tension T.

A fiber optic imaging element includes medium-expansion and a fabrication method including: (1) matching a core glass rod with a cladding glass tube to perform mono fiber drawing; (2) arranging the mono fibers into a mono fiber bundle rod, and then drawing the mono fiber bundle rod into a multi fiber; (3) arranging the multi fiber into a multi fiber bundle rod, and then drawing the multi fiber bundle rod into a multi-multi fiber; (4) cutting the multi-multi fiber, and then arranging the multi-multi fiber into a fiber assembly buddle, then putting the fiber assembly buddle into a mold of heat press fusion process, and performing the heat press fusion process to prepare a block of the fiber optic imaging element with medium-expansion; and (5) edged rounding, cutting and slicing,

In some examples, a microstructured fiber comprises a cladding material surrounding at least one core material, wherein the at least one core material comprises an array of discrete devices contacted in parallel. A method of producing a microstructured fiber may include 3D-printing a fiber preform, thermally drawing the fiber preform into a fiber that preserves the cross-sectional geometry of the fiber preform, and axially patterning the fiber into a microstructured fiber comprising an array of discrete devices contacted in parallel. In some embodiments, microstructured fibers may be integrated into a sensory textile that includes at least one of an electrooptic portion, a sonar portion, a magnetic gradiometer portion, and a piezogenerating portion. In some embodiments, microstructured fibers may be formed into an in-fiber integrated quantum device circuit or an in-fiber ion trap.