公开(公告)号：US12066666B2

公开(公告)日：2024-08-20

申请号：US17420954

申请日：2020-01-06

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Hidenobu Hirota ,  Takui Uematsu ,  Hiroyuki Iida ,  Naotsugu Ambe

IPC: G02B6/38 ,  F21V8/00

CPC classification number: G02B6/3802 ,  G02B6/0006 ,  G02B6/3898

Abstract: An object of the present invention is to provide, in a local-light coupling technique for improving efficiency of work, an optical fiber local-light coupling apparatus configured to hardly affect communication between an OLT and an ONU while causing light to leak from a coated optical fiber in such an amount that makes it possible to confirm a communication state.
The optical fiber local-light coupling apparatus according to the present invention includes a first jig including a concave portion curved in a longitudinal direction with respect to a coated optical fiber, and a probe configured to receive leakage light leaking from the coated optical fiber being bent; a second jig including a convex portion curved in the longitudinal direction with respect to the coated optical fiber, the convex portion being configured to sandwich the coated optical fiber between the convex portion and the concave portion of the first jig; a pressing unit configured to apply pressing force in a direction in which the concave portion of the first jig and the convex portion of the second jig approach each other to form a bend in the coated optical fiber; and a reflective film configured to cover a surface of the concave portion of the first jig except for a leakage light passage portion through which, among the leakage light, reception leakage light to be received by the probe passes, and reflect and return the leakage light other than the reception leakage light to the coated optical fiber.

公开(公告)号：US11711144B2

公开(公告)日：2023-07-25

申请号：US17600537

申请日：2020-03-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hidenobu Hirota ,  Hiroyuki Iida ,  Takui Uematsu ,  Naotsugu Ambe

IPC: H04B10/079 ,  G02B6/28

CPC classification number: H04B10/0795 ,  G02B6/2852

Abstract: There are provided an optical fiber display system and an optical fiber changeover method each enabling an efficient optical fiber changeover work. The optical fiber display system according to the present invention includes a plurality of core wire identification terminals 101. Each of the core wire identification terminals 101 includes: bent part formation units 11 configured to form a bent part at an optional position of an optical fiber 50 and to leak optical signals propagating through the optical fiber 50 from the bent part; analysis units 12 configured to acquire identification numbers of communication apparatuses (51 and 52) included in the leaked optical signals, the communication apparatuses (51 and 52) being connected to respective ends of the optical fiber 50; a communication unit 13 configured to inquire of a database 201 storing relationship between the optical fiber and the communication apparatuses about the acquired identification numbers of the communication apparatuses, and to receive an identification number of the optical fiber 50 corresponding to the acquired identification numbers of the communication apparatuses, from the database 201; and a display unit 14 configured to display the acquired identification numbers of the communication.

公开(公告)号：US12107624B2

公开(公告)日：2024-10-01

申请号：US18010311

申请日：2020-06-26

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Hiroyuki Iida ,  Hidenobu Hirota ,  Takui Uematsu

IPC: H04B10/071

CPC classification number: H04B10/071

Abstract: An object of the present invention is to enable identification of a reflection signal from a terminal portion of an optical fiber to be measured where a reflection signal caused by multiple reflection appears in an OTDR waveform in a mode in which an OTDR and the optical fiber to be measured are connected at a bent portion. The reflection signal caused by multiple reflection inevitably propagates through a distance equal to a distance between true reflection points more than the other reflection point, because of multiple reflection. Therefore, a distance between the reflection signal and another reflection signal is inevitably coincident with a distance between the other reflection signals. In contrast, in a case of a reflection signal from a terminal portion of the optical fiber, the distance between the reflection signal and another reflection signal is not coincident with the distance between the other reflection signals.

公开(公告)号：US12061131B2

公开(公告)日：2024-08-13

申请号：US17595930

申请日：2019-06-03

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hiroyuki Iida ,  Sachi Tsujimura ,  Hidenobu Hirota ,  Takui Uematsu ,  Naotsugu Ambe

IPC: G01M11/00 ,  G01M11/02

CPC classification number: G01M11/0207 ,  G01M11/0228

Abstract: An object is to provide a determination device that determines a state of a terminal end portion of a coated optical fiber at any location of the coated optical fiber. Reflection of test light varies in a reflection amount at each wavelength depending on a situation of the terminal end portion of the coated optical fiber. In other words, if the magnitude of the reflection amount at each wavelength can be known, the situation of the terminal end portion of the coated optical fiber can be estimated. The determination device according to the present invention is configured to make test light having a plurality of wavelengths incident from the optical fiber side and determine the test light based on a light intensity ratio of each reflected light beams reflected at the terminal end. In addition, reflection of test light varies in return loss at each wavelength depending on a situation of the terminal end portion of the coated optical fiber. If Rayleigh backscattered light can also be measured when measuring a reflection amount, the return loss can be known for each wavelength, and the situation of the terminal end portion of the coated optical fiber can be estimated from the result. The determination device according to the present invention is configured to make test light having a plurality of wavelengths incident from the optical fiber side and determine the test light based on a return loss at the terminal end.

公开(公告)号：US11886012B2

公开(公告)日：2024-01-30

申请号：US17427848

申请日：2020-01-22

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui Uematsu ,  Hidenobu Hirota ,  Hiroyuki Iida ,  Naotsugu Ambe

IPC: G02B6/28

CPC classification number: G02B6/2821

Abstract: An object of the present invention is to provide a versatile optical fiber lateral output device that can deal with various types of optical fiber core wires. An optical fiber input-output device according to the present invention includes: a first jig 11 including a recess portion 22 and an optical input-output means 51; a second jig 12 including a projection portion 23 and a guide groove 24; and a pressing unit 14 configured to apply a pressing force in a direction in which the recess portion 22 of the first jig 11 and the projection portion 23 of the second jig 12 approach each other so as to bend an optical fiber core wire 100. Letting R1 be a curvature radius of the recess portion 22 of the first jig 11, θ1 be a central angle of the recess portion 22, R2 be a curvature radius of the projection portion 23 of the second jig 12, and θ2 be a central angle of the projection portion 23, R2≤R1 and θ2≤θ1 are satisfied.

公开(公告)号：US11747564B2

公开(公告)日：2023-09-05

申请号：US17762252

申请日：2019-10-02

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui Uematsu ,  Hidenobu Hirota ,  Hiroyuki Iida ,  Takashi Ebine

IPC: G02B6/28

CPC classification number: G02B6/2826

Abstract: A manufacturing method of an optical splitter of the present disclosure includes: performing first processing that involves mounting a coated optical fiber on a jig configured to store the coated optical fiber, and polishing the coated optical fiber together with the jig until reaching a vicinity of a core of the coated optical fiber or the core of the coated optical fiber; performing second processing that involves applying a refractive index matching material having a refractive index lower than a refractive index of the core of the coated optical fiber onto a polished face of the coated optical fiber on the jig polished in the first processing or onto a polished face of an optical waveguide circuit having been polished in advance until reaching a vicinity of a core or reaching the core, and then bonding the polished faces to each other; and performing third processing that involves positionally aligning the polished faces bonded with each other in the second processing to move the jig or the optical waveguide circuit to a position at which a desired splitting ratio is obtained.

公开(公告)号：US11683091B2

公开(公告)日：2023-06-20

申请号：US17619610

申请日：2019-06-18

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hidenobu Hirota ,  Takui Uematsu ,  Hiroyuki Iida ,  Naotsugu Ambe

IPC: H04B10/079

CPC classification number: H04B10/079

Abstract: The present disclosure has an object to provide a technique for enabling a communication state to be confirmed not in a communication building but in a work site, and to provide a technique for enabling correct splicing between optical cables to be confirmed before fusion splicing. The present disclosure is a communication apparatus identification device 4 including an optical fiber bent portion 42 obtained by, when a portion of optical fibers to which communication apparatuses (the OLT 1-2 and the ONU 2) for which appropriateness of connection is to be determined are connected on opposite ends is bent, bending a portion of the optical fibers in a vicinity of a clearance provided between the optical fibers, the clearance having a range in which the communication apparatuses for which appropriateness of connection is to be determined can communicate with each other, and a MAC address analysis unit 43 that analyzes communication light leaked out of the bent portion of the optical fibers in the vicinity of the clearance to acquire identification numbers (MAC addresses) of the communication apparatuses for which appropriateness of connection is to be determined.

公开(公告)号：US11385127B2

公开(公告)日：2022-07-12

申请号：US17252311

申请日：2019-06-12

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hiroyuki Iida ,  Tetsuya Manabe ,  Yusuke Koshikiya ,  Hidenobu Hirota ,  Takui Uematsu

IPC: G01M11/00 ,  H04B10/071

Abstract: An object of the present disclosure is to provide a frequency division multiplexing coherent OTDR, a test method, a signal processing apparatus, and a program that can maintain, even in a case where a DFB laser is used, a spatial resolution equivalent to a spatial resolution achieved when a fiber laser or an external resonant laser is used. An OTDR according to the present disclosure includes a light incidence unit configured to change an optical frequency of light from a light source by a predetermined frequency interval at a predetermined time interval to generate test light pulses and cause the test light pulses to sequentially enter a fiber under test, a light reception unit configured to use the light from the light source as local light to coherently detect backscattered light from the fiber under test to acquire a received signal, and a computation unit configured to separate the received signal into signals with frequencies obtained by changing the optical frequency by the predetermined frequency interval, square amplitudes of the signals resulting from frequency separation to generate square values, perform Wiener filter processing on the square values, compensate values resulting from the Wiener filter processing for delay time when the test light pulses are caused to enter the fiber under test, and calculate an arithmetic mean of the compensated values.

公开(公告)号：US12242111B2

公开(公告)日：2025-03-04

申请号：US17794710

申请日：2020-02-21

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui Uematsu ,  Hidenobu Hirota ,  Hiroyuki Iida

IPC: G02B6/28 ,  H04B10/61

Abstract: An optical multiplexing and demultiplexing method of the present disclosure includes arranging, face to face, a polished surface of a coated optical fiber whose side surface is polished to a core or a vicinity of the core and a polished surface of an optical waveguide whose propagation constant varies in a longitudinal direction and whose side surface is polished to a core or a vicinity of the core, and aligning the polished surface of the coated optical fiber and the polished surface of the optical waveguide so that desired branching ratio is obtained from one end of the coated optical fiber to the end, distal to the former end, of the optical waveguide by relatively moving the polished surface of the coated optical fiber and the polished surface of the optical waveguide.

公开(公告)号：US11575981B2

公开(公告)日：2023-02-07

申请号：US17271390

申请日：2019-08-23

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui Uematsu ,  Tetsuya Manabe ,  Hidenobu Hirota ,  Hiroyuki Iida

IPC: H04B10/079 ,  H04Q11/00 ,  H04L12/46

Abstract: The present disclosure intends to provide an optical signal from an ONU according to a desired service usage state without using the ONU and an OLT. A simulated signal light generation apparatus 10 according to the present disclosure is a simulated signal light generation apparatus 10 for simulating an uplink signal light generated in an optical network unit (ONU) in a passive optical network (PON), and the apparatus includes a usage state control unit 11 that sets a service usage state of the ONU, a signal generation unit 12 that generates an uplink signal frame according to the usage state set by the usage state control unit 11, and an electrical/optical conversion unit 13 that converts an electrical signal from the signal generation unit 12 into an optical signal, and the optical signal from the electrical/optical conversion unit 13 is repeatedly transmitted to an optical fiber core 22.