公开(公告)号：US11474303B2

公开(公告)日：2022-10-18

申请号：US17279980

申请日：2019-09-11

申请人： Nippon Telegraph and Telephone Corporation

发明人： Masaaki Takaya ,  Yoshiteru Abe ,  Ryo Koyama ,  Chisato Fukai ,  Kazunori Katayama ,  Kazuhide Nakajima ,  Yusuke Yamada

IPC分类号： G02B6/38

摘要： An object is to provide an optical fiber connector ferrule, a sleeve, and a method for manufacturing a ferrule member that can avoid an increase in manufacturing time and an increase in cost of optical connectors for connecting multicore optical fibers. The present invention provides an optical fiber connector ferrule, a sleeve, and a method for manufacturing ferrule member which realizes alignment of multicore optical fibers corresponding to the connection by mounting a ferrule on a multicore fiber and then cutting a ferrule member instead of aligning core positions by rotating an axis of an optical fiber and adjusting positions of cores to the ferrule, leading to simplification of a rotational alignment step.

公开(公告)号：US11366266B2

公开(公告)日：2022-06-21

申请号：US16623608

申请日：2018-07-03

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Yuto Sagae ,  Kazuhide Nakajima ,  Takashi Matsui

IPC分类号： G02B6/02 ,  G02B6/036 ,  H04B10/80

摘要： An optical fiber includes a core, a first clad that is provided on an outer circumferential portion of the core and has a refractive index lower than that of the core, and a second clad that is provided on an outer circumferential portion of the first clad and has a refractive index lower than that of the first clad. In the optical fiber, a mode field diameter at a wavelength of 1.55 μm is equal to or greater than 11.5 μm, a cutoff wavelength is equal to or less than 1.53 μm, a bending loss at a bending radius of 30 mm and a wavelength of 1.625 μm is equal to or less than 2.0 dB/100 turns, and a delay time of transmission light per unit length at a wavelength of 1.55 μm is equal to or less than 4.876 μs/km.

公开(公告)号：US10955622B2

公开(公告)日：2021-03-23

申请号：US16770531

申请日：2018-12-20

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Takashi Matsui ,  Kazuhide Nakajima ,  Masaki Wada ,  Yoko Yamashita

IPC分类号： G02B6/38

摘要： 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.

公开(公告)号：US10585235B2

公开(公告)日：2020-03-10

申请号：US16313724

申请日：2017-06-21

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Taiji Sakamoto ,  Takashi Matsui ,  Kazuhide Nakajima ,  Kotaro Saitoh

IPC分类号： G02B6/38 ,  G02B6/02

摘要： An optical connector is provided which includes at least one multi-core block fixing and holding a plurality of multi-core optical fibers in a state where a position in a direction orthogonal to an optical axis of each multi-core optical fiber and a rotation angle around the optical axis are in a predetermined state, and a ferrule including an accommodating portion accommodating the multi-core block.

公开(公告)号：US11899237B2

公开(公告)日：2024-02-13

申请号：US17294892

申请日：2019-11-08

申请人： Nippon Telegraph and Telephone Corporation

发明人： Takashi Matsui ,  Kazuhide Nakajima

IPC分类号： G02B6/02 ,  G02B27/00

CPC分类号： G02B6/02042 ,  G02B27/0012

摘要： It is an object of the present invention to provide a multicore optical fiber, a design method for the multicore optical fiber and an optical transmission method using the multicore optical fiber including four cores having a standard cladding diameter of 125±1 μm for an existing single mode optical fiber covering several thousands of kilometers of transmission. The multicore optical fiber according to the present invention disposes two-stage claddings with different refractive indices around each core, and designates as a predetermined range, a core radius a1, a radius a2 of a first cladding region surrounding each core, specific refractive index Δ1 relative to the core of the first cladding region and a specific refractive index Δ2 relative to the core of a second cladding region including four cores and the first cladding region.

公开(公告)号：US11860405B2

公开(公告)日：2024-01-02

申请号：US17641061

申请日：2019-09-18

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Saki Nozoe ,  Nobutomo Hanzawa ,  Yuto Sagae ,  Kazuhide Nakajima ,  Kyozo Tsujikawa

IPC分类号： G02B6/02 ,  G02B6/032 ,  G02B6/036

CPC分类号： G02B6/02347 ,  G02B6/02361 ,  G02B6/02366 ,  G02B6/032 ,  G02B6/036

摘要： An object of the present invention is to provide an HAF having a structure in which the number of air holes is decreased to be smaller than that of a PCF and Rayleigh scattering loss may be more reduced than that in the existing HAF. The HAF according to the present invention includes a core portion having a uniform optical refractive index; a cladding portion having a uniform optical refractive index and surrounding the core portion; and a plurality of air holes arranged in two layers at positions configuring hexagonal closest packing excluding the core portion within the cladding portion along a longitudinal direction of the hole-assisted fiber, wherein a center-to-center spacing of the air holes is a sum of a radius Rin of an inscribed circle inscribed in the air holes in an inner layer and a radius d/2 of the air hole, and a radius “a” of the core portion and a relative refractive index difference Δ between the core portion and the cladding portion are present within a range where Rn, which is a ratio of a Rayleigh scattering coefficient Rsmf of a single mode optical fiber and an effective Rayleigh scattering coefficient Reff of the hole-assisted fiber, is equal to or less than 0.92.

公开(公告)号：US11454757B2

公开(公告)日：2022-09-27

申请号：US17260401

申请日：2019-07-11

申请人： Nippon Telegraph and Telephone Corporation

发明人： Taiji Sakamoto ,  Yoshiteru Abe ,  Kazuhide Nakajima

IPC分类号： G02B6/02 ,  G02B6/12 ,  G02B6/122 ,  G02B6/26

摘要： A planar waveguide having M×N number of cores and to which M number of fibers having N number of cores are connected. In the planar waveguide, in a connecting end surface of the planar waveguide to which the fibers are connected, P number of fibers having Q number of cores are connected, M×N is equal to P×Q, the planar waveguide includes a plurality of the cores arranged in a horizontal direction at the same height position in the planar waveguide, and a laminated structure having the cores at different positions in a height direction, so as to be aligned with the cores of the fibers connected to the connecting end surface, and the positions of the M×N number of cores are constant in the height direction, and change only in the horizontal direction.

公开(公告)号：US10790905B2

公开(公告)日：2020-09-29

申请号：US16312051

申请日：2017-07-04

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Takayoshi Mori ,  Taiji Sakamoto ,  Takashi Yamamoto ,  Kazuhide Nakajima ,  Masaki Wada ,  Azusa Urushibara

IPC分类号： H04J14/04 ,  H04B10/2581 ,  G02B6/02 ,  H04B10/50 ,  H04B10/60

摘要： The optical fiber according to the present disclosure is an optical fiber having a pure silica core which is a step index core through which an LPm1 mode with an effective area of 250 μm2 or more is propagated by setting a relative refractive index difference to 0.60% or less, considering an effective cutoff condition, and only 2 or more modes or the LPm1 mode are propagated, with the optical fiber as the transmission line.

公开(公告)号：US10782478B2

公开(公告)日：2020-09-22

申请号：US16322432

申请日：2017-08-01

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Masaki Wada ,  Taiji Sakamoto ,  Takayoshi Mori ,  Shinichi Aozasa ,  Takashi Yamamoto ,  Kazuhide Nakajima

IPC分类号： G02B6/26 ,  H01S3/10 ,  H01S3/067 ,  G02B6/02 ,  G02B6/036

摘要： A differential mode attenuation compensator includes a first multi-mode optical fiber and a third multi-mode optical fiber in which a plurality of propagation modes propagate in a wavelength of a propagating optical signal; and a second multi-mode optical fiber including a core and a clad and arranged with a central axis aligned between the first multi-mode optical fiber and the third multi-mode optical fiber, in which each loss in the plurality of propagation modes is different in the first multi-mode optical fiber and the third multi-mode optical fiber.

公开(公告)号：US10705291B2

公开(公告)日：2020-07-07

申请号：US16327946

申请日：2017-08-25

申请人： NIPPON TELEGRAPH AND TELEPHONE CORPORATION

发明人： Azusa Urushibara ,  Takayoshi Mori ,  Taiji Sakamoto ,  Masaki Wada ,  Takashi Yamamoto ,  Kazuhide Nakajima

IPC分类号： G02B6/02 ,  G02B6/44 ,  G02B6/14 ,  H04B10/2581

摘要： An optical transmission system according to the present disclosure is a mode multiplexed optical transmission system using a multi-mode optical fiber in which a plurality of propagation modes propagate as a transmission line, the optical transmission system including an optical fiber transmission line (83) that includes an optical fiber with two or more propagation modes; and a plurality of mode converters (91) that are configured to generate mode coupling between at least one pair of the propagation modes, in which a variation in an installation interval of the plurality of mode converters (91) is equal to or less than a threshold value determined by the transmission line length (Lt) of the optical fiber transmission line (83).