公开(公告)号：US20250004214A1

公开(公告)日：2025-01-02

申请号：US18707816

申请日：2022-11-10

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Takahito KIRIHARA ,  Satoshi Narikawa ,  Katsuhisa TAGUCHI ,  Ayako IWAKI ,  Kazuhide Nakajima ,  Takashi Matsui ,  Chisato Fukai ,  Yuto SAGAE ,  Tomohiro TANIGUCHI ,  Hiroyuki IIDA

IPC: G02B6/42 ,  A61L2/10 ,  A61L2/24 ,  A61L2/26

Abstract: An object of the present invention is to provide an optical transmission system capable of reducing system costs and reducing waste of output power of a light source. The optical transmission system according to the present invention includes an ultraviolet light source part 11a having a light emitting diode (LED) that outputs ultraviolet light, an optical transmission line 26 that propagates the ultraviolet light through a plurality of cores of a multi-core optical fiber or a plurality of cores of a bundle optical fiber obtained by bundling a plurality of single-core optical fibers, and an optical system 11c that narrows down a spot shape of the ultraviolet light output from the LED to a size including all of the plurality of cores in an optical axis direction, and causes the ultraviolet light to enter the plurality of cores.

公开(公告)号：US20230324623A1

公开(公告)日：2023-10-12

申请号：US18020557

申请日：2020-08-12

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui UEMATSU ,  Hidenobu HIROTA ,  Hiroyuki IIDA

IPC: G02B6/35 ,  G02B6/293 ,  G02B6/26

CPC classification number: G02B6/3594 ,  G02B6/262 ,  G02B6/2938 ,  G02B6/3588

Abstract: The present disclosure is to provide a branch ratio measuring device, a branch ratio measuring method, and an optical multiplexer/demultiplexer circuit manufacturing method that do not require any optical sources for measurement.
A branch ratio measuring device according to the present disclosure includes: an optical waveguide that has a cladding polished to the core or to the vicinity of the core; a first optical intensity measurement unit that is connected to one end of the core of the optical waveguide, and measures an optical intensity; and a second optical intensity measurement unit that is connected to the other end of the core of the optical waveguide, and measures an optical intensity.

公开(公告)号：US20230314715A1

公开(公告)日：2023-10-05

申请号：US18019113

申请日：2020-08-07

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Tatsuya Fujimoto ,  Hidenobu HIROTA ,  Takui UEMATSU ,  Tomohiro Kawano ,  Hiroyuki IIDA ,  Ryo Koyama ,  Tetsuya MANABE ,  Kazunori Katayama

IPC: G02B6/28

CPC classification number: G02B6/2821

Abstract: An object of the present disclosure is to provide an optical coupling device capable of controlling a coupling rate of optical coupling between two coupling optical fibers.
An optical coupling device of the present disclosure includes two coupling optical fibers each including a core and a clad and, between the two coupling optical fibers, a thickness variable member having a thickness between the two coupling optical fibers that varies by irradiation with light.

公开(公告)号：US20210231892A1

公开(公告)日：2021-07-29

申请号：US17266071

申请日：2019-08-09

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Takui UEMATSU ,  Hidenobu HIROTA ,  Hiroyuki IIDA ,  Tetsuya MANABE

IPC: G02B6/42

Abstract: An object is to provide an optical fiber side input and output device in which light can be input and output from the side of the tube core cable without adjusting a spacing S even in a case where the thickness of the protective tube differs, and a method of designing the optical fiber side input and output device. An optical fiber side input and output device according to the present invention has a structure in which an angle of a central angle of an apex portion of a first jig having a convex portion is appropriately set, and a loss insertion is kept equal to or less than a prescribed value by using a relationship between a spacing S at the angle and an insertion loss when light is input and output from the side of the tube core cable, even in a case which a thickness of a protective tube changes, and this eliminates the need of adjusting the spacing S.

公开(公告)号：US20230269005A1

公开(公告)日：2023-08-24

申请号：US18014283

申请日：2020-07-09

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui UEMATSU ,  Hidenobu HIROTA ,  Hiroyuki IIDA

IPC: H04B10/80 ,  H04B10/278

CPC classification number: H04B10/807 ,  H04B10/278

Abstract: An object of the present invention is to provide an optical network system with high electric power efficiency, an operation method thereof, and an optical line terminal device capable of realizing the same.
An optical network system (301) according to the present invention is a bus wiring type optical network system and includes an optical line terminal device (11a) which transmits optical signals (Ls), an optical multiplexer/demultiplexer circuit (12) which inputs some of the optical signals (Ls) to an optical bus core wire (50), and a photoelectric conversion unit (13) which converts the other of the optical signals (Ls) into electric power. The optical network system (301) can effectively utilize the electric power by reusing the electric power wasted in a port (Tf) of an optical fiber coupler.

公开(公告)号：US20230231625A1

公开(公告)日：2023-07-20

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 provide a terminal determination device and a terminal determination method, which enable identification of a reflection signal from a terminal portion of an optical fiber to be measured even in a case 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 51 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：US20230100044A1

公开(公告)日：2023-03-30

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：US20220116109A1

公开(公告)日：2022-04-14

申请号：US17424230

申请日：2020-01-15

Applicant: Nippon Telegraph and Telephone Corporation

Inventor： Takui UEMATSU ,  Hiroyuki IIDA ,  Hidenobu HIROTA ,  Naotsugu AMBE

IPC: H04B10/077

Abstract: Provided are a communication monitoring method and a communication monitoring apparatus capable of an operation of identifying a coated optical fiber regardless of a propagation direction of an optical signal even before communication between an OLT and an ONU is opened. The communication monitoring apparatus according to the present invention includes: an optical signal detection unit 31 configured to receive, as a received signal, at least one of a downlink optical signal transmitted from an OLT 21 or an uplink optical signal transmitted from an ONU 22; and a signal analysis unit 32 configured to detect a signal type and unique information of a transmission source from information included in the received signal, determine whether the received signal is the downlink optical signal or the uplink optical signal on the basis of the signal type, and determine that the unique information of the transmission source is unique information of the OLT when the received signal is the downlink optical signal and that the unique information of the transmission source is unique information of the ONU when the received signal is the uplink optical signal.

公开(公告)号：US20250018518A1

公开(公告)日：2025-01-16

申请号：US18711957

申请日：2021-12-01

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takui UEMATSU ,  Kazutaka NOTO ,  Hiroyuki IIDA ,  Hidenobu HIROTA ,  Kazunori KATAYAMA

IPC: B24B13/00 ,  C03C25/005

Abstract: An object of the present disclosure is to provide an optical multiplexing/demultiplexing circuit manufacturing device and an optical multiplexing/demultiplexing circuit manufacturing method for polishing a portion of a side surface of an optical fiber core wire by a desired polishing amount without measuring optical loss by cutting an active optical fiber core wire.
To achieve the object described above, the optical multiplexing/demultiplexing circuit manufacturing device according to the present disclosure includes: an optical fiber core wire holding unit having a groove in which a portion of a side surface of an optical fiber core wire is embedded so as to protrude from an open plane by a predetermined distance; a polishing unit in which a polishing flat surface facing the open plane in parallel polishes the portion of the side surface of the optical fiber core wire; and a control unit that causes the polishing unit to start polishing the portion of the side surface of the optical fiber core wire and to finish polishing when the polishing flat surface of the polishing unit reaches the open plane.

公开(公告)号：US20240031019A1

公开(公告)日：2024-01-25

申请号：US18028907

申请日：2020-10-14

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Hidenobu HIROTA ,  Takui UEMATSU ,  Hiroyuki IIDA ,  Kazutaka NOTO ,  Kenji INOUE

IPC: H04B10/07 ,  H04B10/25 ,  H04B10/272

CPC classification number: H04B10/07 ,  H04B10/25 ,  H04B10/272

Abstract: An object of the present invention is to provide a monitoring device and an optical fiber identification method capable of efficiently identifying an optical fiber at a construction site.
The monitoring device 71 includes a light receiver 74 that receives an optical signal SL leaked from an optical fiber, a counter 75 that counts the number of unique numbers indicating transmission sources included in the optical signal SL, and a display unit 76 that displays the number of unique numbers. The monitoring device 71 further includes a control unit 77 that causes the display unit 76 to display that a portion where the optical signal SL has leaked is between the 8-branch splitter 51 and the OLT 11 when the number of unique numbers is two or more, and that causes the display unit 76 to display that it is unknown whether a portion where the optical signal SL has leaked is between the 8-branch splitter 51 and the OLT 11 or between the 8-branch splitter 51 and the ONU 21 when the number of unique numbers is one.