公开(公告)号：US09673589B2

公开(公告)日：2017-06-06

申请号：US15236937

申请日：2016-08-15

Applicant: FUJIKURA LTD. ,  NIPPON TELEGRAPH AND TELEPHONE CORPORATION ,  OSAKA PREFECTURE UNIVERSITY PUBLIC CORPORATION

Inventor： Tsukasa Hosokawa ,  Kentaro Ichii ,  Katsuhiro Takenaga ,  Shoichiro Matsuo ,  Hirotaka Ono ,  Makoto Yamada

IPC: H01S3/067 ,  H01S3/094 ,  G02B6/12 ,  H01S3/16

CPC classification number: H01S3/06725 ,  G02B2006/1209 ,  H01S3/0672 ,  H01S3/06729 ,  H01S3/06733 ,  H01S3/06766 ,  H01S3/0804 ,  H01S3/094003 ,  H01S3/094069 ,  H01S3/1603 ,  H01S3/1608

Abstract: An amplification optical fiber operable to propagate light beams in a plurality of modes in a predetermined wavelength range through a core doped with a rare earth element, wherein Expression (1) is satisfied, where a cutoff wavelength of a propagated highest mode light beam is defined as λmax, under conditions in which the cutoff wavelength of the highest mode light beam is defined as λc, a shortest wavelength of the wavelength range is defined as λmin, and a cutoff wavelength of a second-highest mode light beam to the highest mode light beam is λmin. λc>0.5 λmin+0.5 λmax  (1).

公开(公告)号：US20170054266A1

公开(公告)日：2017-02-23

申请号：US15236937

申请日：2016-08-15

Applicant: FUJIKURA LTD. ,  NIPPON TELEGRAPH AND TELEPHONE CORPORATION ,  OSAKA PREFECTURE UNIVERSITY PUBLIC CORPORATION

Inventor： Tsukasa Hosokawa ,  Kentaro Ichii ,  Katsuhiro Takenaga ,  Shoichiro Matsuo ,  Hirotaka Ono ,  Makoto Yamada

IPC: H01S3/067 ,  H01S3/16 ,  H01S3/094

CPC classification number: H01S3/06725 ,  G02B2006/1209 ,  H01S3/0672 ,  H01S3/06729 ,  H01S3/06733 ,  H01S3/06766 ,  H01S3/0804 ,  H01S3/094003 ,  H01S3/094069 ,  H01S3/1603 ,  H01S3/1608

Abstract: An amplification optical fiber operable to propagate light beams in a plurality of modes in a predetermined wavelength range through a core doped with a rare earth element, wherein Expression (1) is satisfied, where a cutoff wavelength of a propagated highest mode light beam is defined as λmax, under conditions in which the cutoff wavelength of the highest mode light beam is defined as λc, a shortest wavelength of the wavelength range is defined as λmin, and a cutoff wavelength of a second-highest mode light beam to the highest mode light beam is λmin. λc>0.5 λmin+0.5 λmax  (1)

公开(公告)号：US20160268757A1

公开(公告)日：2016-09-15

申请号：US15062681

申请日：2016-03-07

Applicant: FUJIKURA LTD. ,  NIPPON TELEGRAPH AND TELEPHONE CORPORATION ,  OSAKA PREFECTURE UNIVERSITY PUBLIC CORPORATION

Inventor： Tsukasa Hosokawa ,  Kentaro Ichii ,  Katsuhiro Takenaga ,  Shoichiro Matsuo ,  Hirotaka Ono ,  Makoto Yamada

IPC: H01S3/067 ,  H01S3/094 ,  H01S3/16

CPC classification number: H01S3/06729 ,  G02B6/03611 ,  H01S3/06766 ,  H01S3/0804 ,  H01S3/094003 ,  H01S3/094069 ,  H01S3/09415 ,  H01S3/1608

Abstract: An optical fiber for amplification includes a core having an inner core and an outer core surrounding the outer circumferential surface of the inner core. The relative refractive index difference of the inner core to a cladding is smaller than the relative refractive index difference of the outer core to the cladding. The outer core is entirely doped with erbium. The theoretical cutoff wavelength of an LP11 mode light beam is a wavelength of 1,565 nm or more. The theoretical cutoff wavelength of an LP21 mode light beam is a wavelength of 1,530 nm or less. The theoretical cutoff wavelength of the LP02 mode light beam is a wavelength of 980 nm or less.

Abstract translation: 用于放大的光纤包括具有内芯和围绕内芯的外圆周表面的外芯的芯。 内芯与包层的相对折射率差小于外芯与包层的相对折射率差。 外芯完全掺铒。 LP11模式光束的理论截止波长为1,565nm以上的波长。 LP21模式光束的理论截止波长为1530nm以下的波长。 LP02模式光束的理论截止波长为980nm以下的波长。

公开(公告)号：US20150234120A1

公开(公告)日：2015-08-20

申请号：US14618147

申请日：2015-02-10

Applicant: FUJIKURA LTD. ,  NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY

Inventor： Hitoshi Uemura ,  Katsuhiro Takenaga ,  Kunimasa Saitoh

IPC: G02B6/02 ,  G02B6/036 ,  G02B6/028

CPC classification number: G02B6/02042 ,  G02B6/028 ,  G02B6/0286 ,  G02B6/0288 ,  G02B6/03611

Abstract: An optical device includes: multiple cores each including an inner core and an outer core surrounding an outer circumferential surface of the inner core without any gap therebetween; and cladding surrounding an outer circumferential surface of the cores without any gap therebetween and having a refractive index lower than that of the outer core, wherein each of the cores has a tapered portion that is tapered from one side toward the other side thereof in a longitudinal direction, each of the inner cores includes a low-refractive-index portion, and a high-refractive-index portion surrounding an outer circumferential surface of the low-refractive-index portion without any gap therebetween and having a refractive index higher than that of the low-refractive-index portion, and the outer core has a refractive index lower than that of the high-refractive-index portion.

Abstract translation: 光学装置包括：多个芯，每个芯包括内芯和围绕内芯的外周表面的外芯，其间没有任何间隙; 并且围绕芯的外周表面的包层，在其之间没有任何间隙，并且折射率低于外芯的折射率，其中每个芯具有从纵向方向的一侧朝向另一侧渐缩的锥形部分 每个内芯包括低折射率部分和围绕低折射率部分的外周表面的高折射率部分，其间没有任何间隙，并且折射率高于 低折射率部分和外芯的折射率低于高折射率部分的折射率。

公开(公告)号：US09069118B2

公开(公告)日：2015-06-30

申请号：US13936624

申请日：2013-07-08

Applicant: FUJIKURA LTD. ,  NAT'L UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY

Inventor： Shoichiro Matsuo ,  Katsuhiro Takenaga ,  Kunimasa Saitoh ,  Masanori Koshiba

IPC: G02B6/036 ,  G02B6/02 ,  G02B6/14 ,  G02B6/255

CPC classification number: G02B6/02042 ,  G02B6/03638 ,  G02B6/14 ,  G02B6/2552

Abstract: A radius of a first core 21 in a large-diameter end surface EF1 of a tapered portion 31 is denoted by r1S, a radius of a second core 22 is denoted by r2S, a relative refractive index difference of the first core 21 with respect to a clad 23 is denoted by Δ1, a relative refractive index difference of the second core 22 with respect to the clad 23 is denoted by Δ2, a refractive index volume of the first core 21 is denoted by V1S, and a refractive index volume of the second core 22 is denoted by V2S, r2S/r1S is set to be 3 or more and 5 or less, V2S/V1S is set to be 1.07r22−13.5 or more and 1.07r22−11.5 or less, and r2S/r1S is set to be −3×Δ1/Δ2+10 or more.

Abstract translation: 锥形部分31的大直径端面EF1中的第一芯21的半径由r1S表示，第二芯22的半径由r2S表示，第一芯21的相对折射率差相对于 包层23由＆Dgr; 1表示，第二芯22相对于包层23的相对折射率差由＆Dgr; 2表示，第一芯21的折射体积由V1S表示，折射率 第二芯22的指标体积由V2S表示，r2S / r1S设定为3以上且5以下，V2S / V1S设定为1.07r22-13.5以上且1.07r22〜11.5V以下，r2S / r1S设置为-3×＆Dgr; 1 /＆Dgr; 2 + 10以上。

公开(公告)号：US09008479B2

公开(公告)日：2015-04-14

申请号：US13846127

申请日：2013-03-18

Applicant: Fujikura Ltd.

Inventor： Shoji Tanigawa ,  Katsuhiro Takenaga

IPC: G02B6/036 ,  G02B6/02

CPC classification number: G02B6/02042

Abstract: A multicore fiber has a plurality of cores; and a clad which surrounds an outer peripheral surface of each of the cores, and at least one of the cores is spirally arranged such that the core rotates around a center axis of the clad. By arranging the cores in this way, it is possible to prevent crosstalk between specific cores from escalating even when the multicore fiber is disposed in a bent state.

Abstract translation: 多芯光纤具有多个芯; 以及围绕每个芯的外周表面的包层，并且至少一个芯螺旋地布置成使得芯围绕包层的中心轴旋转。 通过以这种方式布置芯，即使当多芯纤维处于弯曲状态时，也可以防止特定芯之间的串扰升高。

公开(公告)号：US20140178024A1

公开(公告)日：2014-06-26

申请号：US14194187

申请日：2014-02-28

Applicant: NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY ,  FUJIKURA LTD.

Inventor： Katsuhiro Takenaga ,  Shoichiro Matsuo ,  Yusuke Sasaki ,  Kunimasa Saitoh

IPC: G02B6/02

CPC classification number: G02B6/02042 ,  G02B6/02014 ,  G02B6/02019 ,  G02B6/02366 ,  G02B6/02395 ,  G02B6/0365

Abstract: A multicore fiber for communication 10 which allows propagation of an optical signal includes: a clad 12; a core 11a which is arranged in a center of the clad 12; and seven to ten cores 11b which are arranged at equal intervals surrounding the core 11a, and the cladding diameter is 230 μm, distances between centers of the mutually neighboring cores 11a and 11b are 30 μm or more, distances between the centers of the cores 11b and an outer peripheral surface of the clad 12 are 35 μm or more and a mode field diameter of light propagating in the cores 11a and 11b is 9 μm to 13 μm.

Abstract translation: 用于通信的多芯光纤10，其允许光信号的传播包括：包层12; 布置在包层12的中心的芯11a; 以及围绕芯11a等间隔配置的7〜10个芯11b，包层直径为230μm，相互相邻的芯11a，11b的中心间距离为30μm以上，芯11b的中心间的距离 并且包层12的外周面为35μm以上，在芯11a，11b中传播的光的模场直径为9μm〜13μm。

公开(公告)号：US20220291452A1

公开(公告)日：2022-09-15

申请号：US17633034

申请日：2021-02-22

Applicant: FUJIKURA LTD.

Inventor： Masaki Ohzeki ,  Katsuhiro Takenaga

IPC: G02B6/255 ,  G02B6/02 ,  G06T7/70

Abstract: A method for aligning multicore fiberS that has three or more cores disposed on a circumference centered on a central axis of a clad includes: capturing a first set of images of side surfaces of each of the pair of multicore fibers before and after rotating each of the pair of multicore fibers by P° a number of times (N) rounded up so that N=360/P; determining, for each of the pair of multicore fibers, a similarity between an image of the first set of images before a rotation by P° and an image of the first set of images after the rotation by P° for each of the N times the multicore fiber is rotated by P°; determining specific relative rotation positions of the pair of multicore fibers in which a cross-correlation becomes highest; and rotating at least one of the pair of multicore fibers.

公开(公告)号：US20200369555A1

公开(公告)日：2020-11-26

申请号：US16636820

申请日：2018-08-07

Applicant: Fujikura Ltd.

Inventor： Yoshimichi Amma ,  Katsuhiro Takenaga ,  Ryohei Fukumoto

IPC: C03B37/027 ,  G02B6/02 ,  C03B37/012

Abstract: An optical fiber preform production method includes: inserting at least one glass rod into at least one through-hole that penetrates a cladding glass body that is a cladding of an optical fiber; integrating a dummy rod by either integrating a solid dummy silica rod with a first end of the cladding glass body by heating the first end to close a first opening of the through-hole that opens in the first end, or forming a base end seal that closes the first opening in the first end and integrating the solid dummy silica rod with the base end; and closing a second opening of the through-hole that opens in a second end of the cladding glass body by heating and deforming the second end.

公开(公告)号：US10365429B2

公开(公告)日：2019-07-30

申请号：US15753510

申请日：2016-07-06

Applicant: FUJIKURA LTD. ,  NATIONAL UNIVERSITY CORPORATION HOKKAIDO UNIVERSITY

Inventor： Shota Saito ,  Katsuhiro Takenaga ,  Kunimasa Saitoh ,  Takeshi Fujisawa

IPC: G02B6/02 ,  G02B6/032 ,  G02B6/44

Abstract: A multicore fiber that includes: three or more cores that transmit in single-mode transmission; a common clad that covers a periphery of the three or more cores; and a low-refractive index portion that has a refractive index lower than a refractive index of the clad. The multicore fiber further includes a region having the three or more cores arranged annularly on a cross-section perpendicular to a longitudinal direction. At least a portion of the low-refractive index portion is arranged inside a minimum inscribed circle of two adjacent cores within the region.