公开(公告)号：US20250062585A1

公开(公告)日：2025-02-20

申请号：US18720196

申请日：2022-12-09

Applicant: OFS Fitel, LLC

Inventor： Dan Peter Jakobsen ,  Johannes Vorgod Jorgensen ,  Soren Herstrom ,  Poul Kristensen ,  Simona Ovtar ,  Casper J Schiott

IPC: H01S3/067

Abstract: An optical fiber is formed to include a specialized cladding layer that exhibits a change in refractive index as the fiber is tapered, related to the out-diffusion of a refractive index-decreasing dopant included in the cladding layer. The change in refractive index (propagation constant) is sufficient to maintain the local taper angle relation and prevent the institution of loss oscillations as the length of the taper extends to a desired value. In particular, the specialized cladding layer may be formed to include a sufficient concentration of an index-decreasing dopant such as F, which is known to diffuse faster that the conventional cladding layer index-increasing dopants (e.g., one or more of Ge, Cl, and P).

公开(公告)号：US20240353613A1

公开(公告)日：2024-10-24

申请号：US18688306

申请日：2022-08-29

Applicant: OFS Fitel, LLC

Inventor： Tristan Kremp ,  Jie Li ,  Jiawei Luo ,  Andrei A Stolov

IPC: G02B6/028 ,  C03C3/06 ,  C03C13/04 ,  G02B6/036

CPC classification number: G02B6/0288 ,  C03C3/06 ,  C03C13/046 ,  C03C2201/31 ,  C03C2213/00 ,  G02B6/036

Abstract: A hydrogen diffusion barrier is included as an intra-cladding layer (i.e., a “ring”) within an optical fiber structure. The hydrogen diffusion barrier ring may comprise alumina (or other glass oxides) and is positioned within the fiber cladding at an optimum location with respect to the central core region of the optical fiber. The thickness of the barrier ring may be controlled by fabrication processes to control properties such as hydrogen permeability. Other alkali and alkaline earth metal oxides may be included in the composition of the barrier ring and are useful in preventing crystal formation during the fiber fabrication process.

公开(公告)号：US20240275121A1

公开(公告)日：2024-08-15

申请号：US18567824

申请日：2022-06-09

Applicant: OFS Fitel LLC

Inventor： Andrew T Grimes ,  Anand Hariharan ,  Jeffrey W Nicholson

IPC: H01S3/16 ,  H01S3/00 ,  H01S3/067 ,  H01S3/094 ,  H01S3/30 ,  H04J14/02

CPC classification number: H01S3/1608 ,  H01S3/0078 ,  H01S3/06754 ,  H01S3/094046 ,  H01S3/302 ,  H04J14/0221

Abstract: Embodiments of the present disclosure generally relate to systems, methods, and articles of manufacture for using a fiber laser with wavelength division multiplexers (WDMs) for a variety of purposes. For example, implementations described herein may be used with high-power Raman fiber laser (RFL) systems, or the like. A laser system is provided that may include a fiber laser; a laser path comprising optical fiber; and a plurality of wavelength division multiplexers (WDMs) positioned within the laser path coupling the optical fiber; wherein at least one of the plurality of WDMs has the widest wavelength spacing and is positioned first in the laser path, thereby providing increased power stability.

公开(公告)号：US20240134121A1

公开(公告)日：2024-04-25

申请号：US18220015

申请日：2023-07-10

Applicant: OFS Fitel, LLC

Inventor： Tristan Kremp ,  Yue Liang ,  Robert L Lingle

IPC: G02B6/255

CPC classification number: G02B6/2555

Abstract: A system of aligning concatenated sections of multicore optical fiber incorporates the capability of intentionally changing core assignments as part of the azimuthal alignment process. The intentional changing of core assignments, referred to as offset clocking, compensates for differences in properties of the individual core regions in a way that reduces variations between the spatial channels supported in the transmission system. The offset clocking technique can be used, e.g., to improve the attenuation (or other selected properties of the propagating signals). The offset clocking technique may be used to step through sequential changes core assignments at one or more splice locations (passive clocking) or identify a particular pairing of cores from one fiber section to the next (e.g., “good quality” core assigned to a “poor quality” signal exiting the first section) and rotate the fiber sections with respect to each other to achieve this particular core assignment.

公开(公告)号：US20240126009A1

公开(公告)日：2024-04-18

申请号：US18276915

申请日：2022-02-14

Applicant: OFS FITEL, LLC

Inventor： Raja A Ahmad ,  Paul S Westbrook

IPC: G02B6/02

CPC classification number: G02B6/02147

Abstract: Described herein are systems, methods, and articles of manufacture for high back-scattering waveguides (e.g., optical fibers) and sensors employing high back-scattering optical fibers. Briefly described, one embodiment comprises a high back-scattering fiber, or enhanced scattering fiber or “ESF,” that features resistance specifications that remain intact over lengths of fiber in excess of 1 m, or preferably >100 m, or preferably >1 km, wherein the reflectivity of the ESFs may be precisely tuned within a range from −100 dB/mm to −70 dB/mm, and wherein the enhanced scattering may be spatially continuous or, alternatively, may be at discrete locations spaced apart by 100 microns to >10 m.

公开(公告)号：US11933600B2

公开(公告)日：2024-03-19

申请号：US17288971

申请日：2019-11-18

Applicant: OFS FITEL, LLC

Inventor： Raja A Ahmad ,  Kenneth S Feder ,  Wing Ko ,  Paul S Westbrook

IPC: G01B11/16 ,  G01B11/24

CPC classification number: G01B11/161 ,  G01B11/2441

Abstract: An extended length of optical fiber having an offset core with an inscribed Bragg grating is used a distributed sensor in combination with an optical frequency domain reflectometer (OFDR) to enable measurement small-scale (e.g., sub-millimeter) contortions and forces as applied to the fiber. The offset core may be disposed in a spiral configuration around the central axis of the optical fiber to improve the spatial resolution of the measurement. A reference surface exhibit a predetermined texture (in the form of a series of corrugations, for example, that may be periodic or aperiodic, as long as known a priori) is disposed adjacent to a longitudinal portion of the sensor fiber. The application of a force to the combination of the plate and the fiber creates a local strain in the grating formed along the offset core of the fiber that results in a shift in the Bragg wavelength of the grating. Using ODFR measurement techniques, an analysis of the Bragg wavelength shift allows for a high resolution force measurement to be obtained.

公开(公告)号：US20240053560A1

公开(公告)日：2024-02-15

申请号：US18267439

申请日：2020-12-17

Applicant: OFS Fitel, LLC

Inventor： Harold P Debban ,  Henson P Toland ,  Peter A Weimann

IPC: G02B6/44 ,  G02B6/52

CPC classification number: G02B6/443 ,  G02B6/52

Abstract: Embodiments of the invention include an optical fiber cable. The optical fiber cable includes a multi-fiber unit tube that is substantially circular and dimensioned to receive a plurality of optical fibers. The optical fiber cable also includes a plurality of partially bonded optical fiber ribbon units positioned within the multi-fiber tube. The partially bonded optical fiber ribbon units are partially bonded in such a way that each partially bonded optical fiber ribbon is formed in a substantially circular shape or a random shape. The optical fiber cable also includes at least one elastomeric strength layer formed around the partially bonded optical fiber ribbon units. The optical fiber cable also includes an outer jacket surrounding the multi-fiber tube.

公开(公告)号：US11740403B2

公开(公告)日：2023-08-29

申请号：US17289164

申请日：2019-12-03

Applicant: OFS FITEL, LLC

Inventor： Hongchao Wu

IPC: G02B6/02 ,  C03C25/105 ,  G01K11/3206 ,  C08G77/20

CPC classification number: G02B6/02395 ,  C03C25/105 ,  G01K11/3206 ,  G02B6/021 ,  C08G77/20

Abstract: An optically transparent protective coating is described that remains stable at elevated temperatures associated with optical fiber-based sensor applications and is sufficiently transparent to allow for conventional fiber Bragg gratings (FBGs) to be formed by directly writing through the coating. In particular, vinyl group-containing silicone polymers have been found to provide the UV transparency required for a write-through coating (WTC) and promising mechanical properties for protecting the optical fibers, while also being able to withstand elevated temperatures for extended periods of time.

公开(公告)号：US20230086950A1

公开(公告)日：2023-03-23

申请号：US17948378

申请日：2022-09-20

Applicant: OFS Fitel, LLC

Inventor： Kelvin B. Bradley

IPC: G02B6/38 ,  G02B6/44

Abstract: An optical connector for terminating a cable containing one or more multicore fibers. The connector has a plug housing, a ferrule disposed inside the housing, a rotatable frame, and a multicore fiber (MCF) stub having a length of a first MCF a portion of which is fixed inside the ferrule so that a first endface of the fiber is exposed at the front end of the ferrule. An opposite endface of the first MCF is cleaved for fusion splicing to a second MCF in the cable to be terminated. The ferrule also has a flange, and the frame is formed to engage the flange for rotation so that cores in the first MCF can be aligned and positioned in a prescribed orientation relative to the plug housing, and cores in the second MCF can be aligned with corresponding cores in the first MCF when the first and the second MCFs are fusion spliced to one another.

公开(公告)号：US20230036344A1

公开(公告)日：2023-02-02

申请号：US17790636

申请日：2021-01-11

Applicant: OFS FITEL, LLC

Inventor： Andrei A Stolov ,  Paul S Westbrook

IPC: G02B6/02 ,  C03B37/025 ,  C03C25/104

Abstract: Described herein are systems, methods, and articles of manufacture for a spatially nonuniform scattering profile along its length, whose backscattering signal can be used for sensing even after fiber attenuation increases due to the conditions in the sensing environment. In one embodiment, the fiber has been pre-exposed to the conditions that produce attenuation, and the spatially nonuniform profile compensates for this. Subsequent exposure then results in very little or at least acceptable levels of additional attenuation. An exemplary fiber comprises a fiber length and an optical back scatter along the fiber length greater than a Rayleigh back scattering over the fiber length, wherein the optical back scatter does not decrease along the fiber length by more than 3 dB after exposure to a hydrogen-rich first environment having a given pressure and temperature. An exemplary method comprises drawing a fiber, applying a UV coating, post-processing the fiber using an interferogram, measuring optical back scatter enhancement dependence based on a UV dosage, incrementally increasing the reflectivity, exposing the fiber to a hydrogen-rich first environment.