公开(公告)号：US20250141174A1

公开(公告)日：2025-05-01

申请号：US18836969

申请日：2022-02-17

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Taiji SAKAMOTO ,  Ryota IMADA ,  Shinichi AOZASA ,  Kazuhide NAKAJIMA

IPC: H01S3/094 ,  H01S3/067

Abstract: The present disclosure is an optical fiber amplifier including: an amplification optical fiber doped with a rare earth element, in which a pump light combiner for injecting multimode pump light into a cladding region of the amplification optical fiber is connected to an input end or an output end of the amplification optical fiber, and a reflective device for reflecting the pump light and transmitting signal light is connected to an end part, of the amplification optical fiber, to which the pump light combiner is not connected.

公开(公告)号：US20250105578A1

公开(公告)日：2025-03-27

申请号：US18833531

申请日：2022-02-17

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Taiji SAKAMOTO ,  Ryota IMADA ,  Shinichi AOZASA ,  Kazuhide NAKAJIMA

IPC: H01S3/067 ,  H01S3/094

Abstract: An amplification optical fiber according to the present disclosure is an amplification optical fiber doped with a rare earth element, the amplification optical fiber including: a first cladding enclosing cores of the amplification optical fiber; and a second cladding enclosing the first cladding, in which the two or more cores are disposed inside the first cladding in a cross section of the amplification optical fiber, and a core cladding ratio Rcc, which is a ratio of a sum of areas of the two or more cores to a sum of areas of the two or more cores and the first cladding in the cross section of the amplification optical fiber, is 0.0095

公开(公告)号：US20230163554A1

公开(公告)日：2023-05-25

申请号：US17913097

申请日：2020-03-30

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Shinichi AOZASA ,  Yoko YAMASHITA ,  Takashi MATSUI ,  Kazuhide NAKAJIMA ,  Taiji SAKAMOTO ,  Nobutomo HANZAWA ,  Noriyuki ARAKI ,  Ryota IMADA ,  Yuto SAGAE

IPC: H01S3/067 ,  G02B6/32 ,  G02B3/08

CPC classification number: H01S3/06754 ,  G02B3/08 ,  G02B6/32 ,  H01S3/1608

Abstract: An object of the present disclosure is to implement a clad-excitation rare-earth-added optical fiber amplifier with a high light-to-light conversion efficiency. The present disclosure is an optical fiber amplifier having, in a longitudinal direction of a rare-earth-added optical fiber, a light collection structure that collets an excitation light, which propagates through a clad portion, into a core portion.

公开(公告)号：US20190245317A1

公开(公告)日：2019-08-08

申请号：US16343357

申请日：2017-10-25

Applicant: NIPPON TELEGRAPH AND TELEPHONE CORPORATION

Inventor： Masaki WADA ,  Shinichi AOZASA ,  Taiji SAKAMOTO ,  Takashi YAMAMOTO ,  Kazuhide NAKAJIMA ,  Takayoshi MORI

IPC: H01S3/067 ,  H01S3/106 ,  H04B10/2581

CPC classification number: H01S3/06791 ,  H01S3/067 ,  H01S3/0675 ,  H01S3/06754 ,  H01S3/10 ,  H01S3/106 ,  H04B10/2581

Abstract: An optical amplifier of the present disclosure includes an optical resonator that includes an amplification fiber capable of amplifying signal light having one or more propagation modes and resonates at least one propagation mode of the signal light amplified by the amplification fiber; an excitation light source that outputs excitation light for exciting the amplification fiber; and a multiplexer that multiplexes the signal light and the excitation light, in which the optical resonator includes a gain clamp setting unit which sets gain clamp for at least one propagation mode out of a plurality of propagation modes resonating in the optical resonator.