公开(公告)号：US20230042437A1

公开(公告)日：2023-02-09

申请号：US17791930

申请日：2020-02-19

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yoko YAMASHITA ,  Kazuhide NAKAJIMA ,  Takashi MATSUI

IPC: H01S3/067

Abstract: An object of the present disclosure is to allow gain compensation with a simple configuration without adding a new device to the outside. The present disclosure discloses a rare earth doped fiber including a core doped with a rare earth and a cladding region around the core, wherein one or more cavities are provided inside the core, and at least one of the cavities are provided along a longitudinal direction of the rare earth doped fiber.

公开(公告)号：US20240272375A1

公开(公告)日：2024-08-15

申请号：US18570431

申请日：2021-06-21

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yoshiteru ABE ,  Yoko YAMASHITA ,  Taiji SAKAMOTO ,  Takashi MATSUI ,  Kazuhide NAKAJIMA ,  Kazunori KATAYAMA

IPC: G02B6/38

CPC classification number: G02B6/3882

Abstract: An object of the present disclosure is to connect an optical fiber and an optical waveguide with a low loss. The present disclosure is an optical connector plug, including: an optical waveguide having two guide pin V-grooves engraved on one surface thereof and having a cross section of one or more cores appearing between cross sections of the guide pin V-grooves on one end face thereof; two guide pins separately arranged in the two guide pin V-grooves; a flat substrate so fixed as to tuck the two guide pins in the two guide pin V-grooves on the one surface of the optical waveguide; and a fixing member equipped with the optical waveguide, the two guide pins, and the flat substrate.

公开(公告)号：US20240142696A1

公开(公告)日：2024-05-02

申请号：US18277320

申请日：2021-02-17

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yoko YAMASHITA ,  Takayoshi MORI ,  Takashi MATSUI ,  Kazuhide NAKAJIMA

IPC: G02B6/02 ,  G02B27/00

CPC classification number: G02B6/02095 ,  G02B27/0012

Abstract: An objective of the present invention is to provide a mode conversion device capable of designing any coupling efficiency and full width at half maximum, and a design method therefor.
According to the present invention, a mode conversion device includes a long period grating at a core of an optical fiber through which light is able to propagate in at least two propagation modes. The long period grating satisfies a relationship of Expression C1, where a full width at half maximum FWHM is a wavelength band in which the coupling efficiency is a half of coupling efficiency of mode conversion at a center wavelength, C is coupling efficiency, Lc is a complete coupling length, Lg is a grating length, Λ is a grating pitch, and Δβ is a propagation constant difference between the two propagation modes at the center wavelength of a mode conversion target.







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公开(公告)号：US20230400625A1

公开(公告)日：2023-12-14

申请号：US18026359

申请日：2020-09-18

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yoko YAMASHITA ,  Takashi MATSUI ,  Kazuhide NAKAJIMA

IPC: G02B6/02 ,  G02B6/36

CPC classification number: G02B6/022 ,  G02B6/36

Abstract: An object is to provide an optical side input/output circuit that has wavelength selectivity and is easily disposed at multiple points in a transmission path, and an optical connector.
An optical side input/output circuit 301 according to the present invention includes: a grating portion 20 in which a fiber Bragg grating 21 that reflects light of a desired wavelength is formed in the core 51 of an optical fiber 50, the light of the desired wavelength being of light propagating in the core 51; and a tap portion 10 that is disposed at a stage before the grating portion 20 in the propagation direction of the light, and is provided with a tap waveguide 53 that outputs the light reflected by the grating portion 20 from a side surface of the optical fiber 50.

公开(公告)号：US20230358966A1

公开(公告)日：2023-11-09

申请号：US18026381

申请日：2020-09-18

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Yoko YAMASHITA ,  Takashi MATSUI ,  Kazuhide NAKAJIMA

IPC: G02B6/34

CPC classification number: G02B6/34

Abstract: The present invention aims to provide an optical side input/output circuit that has wavelength selectivity and is easily disposed at multiple points in a transmission path, and an optical connector.
The optical side input/output circuit 301 includes: a tap portion 10 in which a tap waveguide 53 that outputs light of a higher-order mode from a side surface of an optical fiber 50 is formed, the light of the higher-order mode being of light propagating in the core 51 of the optical fiber 50; and a grating portion 20 that is located in a stage before the tap portion 10 in the propagation direction of the light, and has a grating 21 that converts light of a desired wavelength from a basic mode to the higher-order mode, the grating 21 being formed in the core 51 of the optical fiber 50.

公开(公告)号：US20200379187A1

公开(公告)日：2020-12-03

申请号：US16770531

申请日：2018-12-20

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Takashi MATSUI ,  Kazuhide NAKAJIMA ,  Masaki WADA ,  Yoko YAMASHITA

IPC: G02B6/38

Abstract: According to the connection device, the connection method, the optical connector manufacturing device, and the method for manufacturing an optical connector, rotation alignment of an MCF becomes unnecessary because an image of an end surface of the MCF to be connected is captured, the position of the core is located, and an optical waveguide is formed on a substrate so as to match the position. Thus, it is possible to solve the problem of increasing loss or complex connection work caused by rotational misalignment in association with rotation alignment.