-
1.发明申请公开(公告)号：US20230137926A1
公开(公告)日：2023-05-04
申请号：US17911071
申请日：2021-03-15
Applicant: OFS Fitel, LLC
Inventor： Raja A Ahmad , Paul S Westbrook
Abstract: A system for sensing microbends and micro-deformations in three-dimensional space is based upon a distributed length optical fiber formed to include a group of offset cores disposed in a spiral configuration along the length of the fiber, each core including a fiber Bragg grating that exhibits the same Bragg wavelength. A micro-scale local deformation of the multicore fiber produces a local shift in the Bragg wavelength, where the use of multiple cores allows for a complete micro-scale modeling of the local deformation. Sequential probing of each core allows for optical frequency domain reflectometry (OFDR) allows for reconstruction of a given three-dimensional shape, delineating location and size of various microbends and micro-deformations.
-
公开(公告)号：US20210389121A1
公开(公告)日：2021-12-16
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
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：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.
-
Patent Agency Ranking
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
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.
-
5.发明授权公开(公告)号：US10261246B2
公开(公告)日：2019-04-16
申请号：US15474189
申请日：2017-03-30
Applicant: OFS Fitel, LLC
Inventor： Raja A Ahmad , Man F Yan , David J DiGiovanni
Abstract: A higher-order mode (HOM) fiber is configured as a polarization-maintaining fiber by including a pair of stress rods at a location within the cladding layer that provides for a sufficient degree of birefringence without unduly comprising the spatial mode profile of the propagating higher-order modes. Long-period gratings are used as mode couplers at the input and output of the PM-HOM fiber, where the gratings are formed by exposing areas of the core region orthogonal to the position of the stress rods. The diameter of the stress rods (D) and displacement of the rods from the center of the core region (R1) are controlled to yield a configuration with an acceptable birefringence and polarization extinction ratio (PER) within the HOM fiber, even in situations where the fiber is bent (a bend radius less than 50 cm).
-
公开(公告)号：US12019292B2
公开(公告)日：2024-06-25
申请号：US17415571
申请日：2019-12-16
Applicant: OFS Fitel, LLC
Inventor： Raja A Ahmad , David J DiGiovanni
CPC classification number: G02B6/43 , G02B6/4212
Abstract: A photoinduced refractive index-changing material is coupled directly to both a first port and a second port. An optical interconnect structure (for optically coupling the first port to the second port) is formable in the photoinduced refractive index-changing material by selectively exposing a portion of the photoinduced refractive index-changing material. The selective exposure induces a refractive index change in the photoinduced refractive index-changing material. The change in refractive index provides the waveguiding properties of the optical interconnect structure.
-
公开(公告)号：US20220057586A1
公开(公告)日：2022-02-24
申请号：US17415571
申请日：2019-12-16
Applicant: OFS Fitel, LLC
Inventor： Raja A Ahmad , David J DiGiovanni
Abstract: A photoinduced refractive index-changing material is coupled directly to both a first port and a second port. An optical interconnect structure (for optically coupling the first port to the second port) is formable in the photoinduced refractive index-changing material by selectively exposing a portion of the photoinduced refractive index-changing material. The selective exposure induces a refractive index change in the photoinduced refractive index-changing material. The change in refractive index provides the waveguiding properties of the optical interconnect structure.
-
8.发明授权公开(公告)号：US11156769B2
公开(公告)日：2021-10-26
申请号：US16384791
申请日：2019-04-15
Applicant: OFS Fitel, LLC
Inventor： Raja A Ahmad , Man F Yan , David J DiGiovanni
Abstract: A higher-order mode (HOM) fiber is configured as a polarization-maintaining fiber by including a pair of stress rods at a location within the cladding layer that provides for a sufficient degree of birefringence without unduly comprising the spatial mode profile of the propagating higher-order modes. An optical imaging system utilizing polarization-maintaining HOM fiber allows for different wavelength probe signals to be directed into different modes, useful in applications such as STED microscopy, 2D sensing, and the like.
-
-
-
-
-
-
-
Search Results
8
records
(took 0.012 seconds)
