专利快速检索-快速检索全球专利，免费商用专利数据库-IPRDB

21. 发明专利

JP2002217478A OPTICAL AMPLIFIER 失效
公开(公告)号：JP2002217478A
公开(公告)日：2002-08-02
申请号：JP2001012129
申请日：2001-01-19
申请人： NIPPON TELEGRAPH & TELEPHONE , NTT ELECTRONICS CORP
发明人： ONO HIROTAKA , SAKAMOTO TADASHI , SHIMIZU MAKOTO , NISHIDA YOSHIKI
IPC分类号： H01S3/131 , H01S3/06 , H01S3/067 , H04B10/07 , H04B10/079 , H04B10/29 , H04B10/294 , H04B10/08 , H04B10/16 , H04B10/17
摘要： PROBLEM TO BE SOLVED: To provide an optical amplifier which will not generate a false alarm, even if the level of gain changes in the optical amplifier performing automatic control, and will not exert influence on a network operation system. SOLUTION: In the optical amplifier repeating optical transmission, a reference value generating circuit 11 changes a reference value which is given to a comparator 9 according to the input power to the optical amplifier. The reference value is given to the comparator 9, in such a manner that an output gain is constant when the input power is small and the output is constant, when the input power is rather large. Generally, since there is the optical amplifier has a limit in the maximum output, a device may generate a false alarm, even though sufficient output power is attempted. That is, when operation of constant gain is to be always realized, the target gain cannot be obtained in the case that the input power is large to some degree. By this constitution, the false alarm like this is not generated, and stable system operation is enabled.

22. 发明专利

JP2001119347A OPTICAL COMMUNICATION NODE AND OPTICAL COMMUNICATION SYSTEM 失效
公开(公告)号：JP2001119347A
公开(公告)日：2001-04-27
申请号：JP2000239959
申请日：2000-08-08
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： ONO HIROTAKA , SHIMANO KATSUHIRO , KUWANO SHIGERU , JINNO MASAHIKO
IPC分类号： H04B10/00 , H04B10/03 , H04B10/032 , H04B10/077 , H04B10/079 , H04B10/25 , H04B10/27 , H04B10/275 , H04B10/296 , H04B10/532 , H04B10/548 , H04B10/564 , H04B17/00 , H04B10/02
摘要： PROBLEM TO BE SOLVED: To provide an optical communication node with which stable control is realized even if abnormality occurs in a control light source system and to provide an optical communication system using the node. SOLUTION: In an optical communication node provided with a multiplexer multiplexing plural signal light beams and multiplexing a signal light beam and a control light beam, a demultiplexer demultiplexing the plural signal light beams and demultiplexing the signal light beam and the control light beam, an optical switch branching and inserting the signal light beam or changing over the path of the signal light beam, an optical attenuator adjusting the light level of the signal light beam, a light transmitter transmitting the signal light beam and an optical receiver receiving the signal light beam, at least one or above control light source for controlling light amplifier and at least one ore above coupling/branching means coupling/branching control light power emitted from the control light source are installed. Branched control light power is guided to the multiplexer.

23. 发明专利

JPH1012952A OPTICAL FIBER AMPLIFIER 失效
公开(公告)号：JPH1012952A
公开(公告)日：1998-01-16
申请号：JP15934896
申请日：1996-06-20
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： ONO HIROTAKA , YAMADA MAKOTO , SUDO SHOICHI , NAKAGAWA KOICHI
IPC分类号： G02F1/35 , H01S3/06 , H01S3/10 , H04B10/2507 , H04B10/29 , H04B10/291 , H04B10/40 , H04B10/50 , H04B10/60 , H04B10/02 , H04B10/16 , H04B10/17 , H04B10/18
摘要： PROBLEM TO BE SOLVED: To provide amplification characteristics of low noise with a wide band and a flat gain, by constituting an amplification section with three stages of an initial-stage amplification section, an intermediate-stage amplification section and a latter-stage amplification section, and causing an optical amplification medium of at least one of the three stages to be made of an Er -added fluorophosphoric acid fiber. SOLUTION: Amplification optical fibers 1-1, 1-2, 1-3, excitation light sources 2-1, 2-2, 2-3, demultiplexers 3-1, 3-2, 3-3, and optical isolators 4-1, 4-2, 4-3, 4-4 constitute a main section. As the amplification optical fiber 1-2, an Er -doped fluorophosphoric acid fiber is used. As the excitation light sources 2-1 and 2-2, strained quantum well semiconductor lasers are used. As the demultiplexers 3-1, 3-2 and 3-3, WD fiber couplers are used. As the optical isolators 4-1, 4-2, 4-3 and 4-4, optical isolators of polarization-independent type are used.

24. 发明专利

JPH09211505A OPTICAL FIBER AMPLIFIER 失效
公开(公告)号：JPH09211505A
公开(公告)日：1997-08-15
申请号：JP1449796
申请日：1996-01-30
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： ONO HIROTAKA , NAKAGAWA KOICHI , SUDO SHOICHI , YAMADA MAKOTO , SAKAMOTO TADASHI
IPC分类号： G02F1/35 , H01S3/06 , H01S3/094 , H01S3/10
摘要： PROBLEM TO BE SOLVED: To embody low noises and an amplification characteristic of a wide band by using an erbium added fluorophosphate glass fiber as an amplifier medium and using a light source for exciting the specific level of erbium as an exciting light source. SOLUTION: This optical fiber amplifier 1 is formed by using the erbium added fluorophosphate glass fiber as an amplifier medium and using the exciting light sources 2-1, 2-2 for exciting the I11/2 level of erbium. The spectra of the band corresponding to the sub-level by Stark fissure of the I13/2 level and the I15/2 level by a crystal field appears in the transition from the I13/2 level of erbium to the I15/2 . Phonon energy is higher with the erbium added fluorophosphate glass fiber than a fluoride optical fiber and, therefore, the life of the I11/2 level of erbium is shorter and the electrons excited at the I11/2 level are non-radiantly relaxed to the I13/2 level. Then, the lower noise is made possible by effecting excitation by using the light source for exciting the I11/2 level of erbium.

25. 发明专利

JP2010224155A DISPERSION COMPENSATOR 审中-公开
公开(公告)号：JP2010224155A
公开(公告)日：2010-10-07
申请号：JP2009070520
申请日：2009-03-23
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： MINO SHINJI , TAKAHASHI HIROSHI , OBA NAOKI , ISHII MOTOHAYA , SENOO KAZUNORI , WATANABE TOSHIO , ONO HIROTAKA
IPC分类号： G02F1/061 , G02F1/13 , H04B10/2507 , H04B10/2513
摘要： PROBLEM TO BE SOLVED: To solve the problems that the size of one side of a spatial phase modulation element becomes larger in accordance with channel increase, however, the size increase of the spatial phase modulation element is not preferable from the viewpoint of mass productivity and manufacturing costs, and when a variable dispersion compensator is constituted by using the spatial phase modulation element, light transmission falls off in an optical frequency (wavelength) corresponding to an edge of an FSR of an AWG, with respect to a variable dispersion compensator which performs dispersion compensation independently of each channel using the spatial phase modulation element. SOLUTION: The multichannel variable dispersion compensator is constituted by combining a plurality of variable dispersion compensators (TODC) using the spatial phase modulation element whose size in the direction corresponding to a spectacle axis of the AWG is suppressed as short. In a communication system using a group branching filter, the FSR is set so as to satisfy predetermined relation with all bandwidths of a WDM communication channel group to be covered by a TODC block to flatten optical transmission characteristics. COPYRIGHT: (C)2011,JPO&INPIT

26. 发明专利

JP2002057389A OPTICAL AMPLIFIER 失效
公开(公告)号：JP2002057389A
公开(公告)日：2002-02-22
申请号：JP2001168798
申请日：2001-06-04
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： YAMADA MAKOTO , ONO HIROTAKA , KANAMORI TERUHISA , OISHI YASUTAKE
IPC分类号： G02B6/00 , H01S3/06 , H01S3/067 , H01S3/07 , H01S3/10 , H04B10/25 , H04B10/29 , H04B10/294 , H04J14/00 , H04J14/02 , H04B10/16 , H04B10/17
摘要： PROBLEM TO BE SOLVED: To provide an optical amplifier having flat and wide band amplifying characteristics. SOLUTION: The optical amplifier comprises a branch unit 2 for branching a signal light into a plurality of wavelength bandwidths, a plurality of optical amplifying units 1-1 and 1-2 for amplifying the signal light of the respective wavelength bandwidths to be output from the branch unit, and a multiplexer 4 for multiplexing the light output from the plurality of the amplifying units.

27. 发明专利

JP2001197010A OPTICAL AMPLIFIER, NODE DEVICE, AND OPTICAL COMMUNICATION NETWORK SYSTEM 失效
公开(公告)号：JP2001197010A
公开(公告)日：2001-07-19
申请号：JP2000000507
申请日：2000-01-05
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： ONO HIROTAKA , SHIMANO KATSUHIRO
IPC分类号： H04B10/079 , H04B10/2507 , H04B10/275 , H04B10/29 , H04B10/293 , H04B10/296 , H04B10/564 , H04B10/572 , H04B17/00 , H04J14/00 , H04J14/02 , H04B10/17 , H04B10/04 , H04B10/06 , H04B10/14 , H04B10/16
摘要： PROBLEM TO BE SOLVED: To provide an optical amplifier, a node device, and an optical communication network system which can accurately monitor and surely control the light power level of a wavelength multiplex signal without increasing the device scale nor being affected by ASE. SOLUTION: An input light signal is branched by an optical branch unit 21 and demultiplexed by a demultiplexer 7 to respective wavelengths, optical detectors 8b1 to 8b16 detect the light power values of respective input light signals, and a detection control circuit 19 detects light power level information and wavelength number information on the respective wavelengths of the input light signals and the output light signal amplified by an optical amplification part 1 is demultiplexed by the demultiplexer 7 to respective wavelengths, optical detectors 8a1 to 8a16 detect the light power values of respective output demultiplexed signals, and a detection control circuit 92 detect light power level information and wavelength number information on the respective wavelengths of the output light signals. Then a control circuit 5 performs control according to the light power level information and wavelength number information on the respective wavelengths of the input light signals and the light power level information and wavelength number information on the respective wavelengths of the output light signals so that the gains of the respective wavelengths at the optical amplification part 1 are held constant.

28. 发明专利

JPH10229238A OPTICAL FIBER AMPLIFIER AND OPTICAL AMPLIFYING METHOD 失效
公开(公告)号：JPH10229238A
公开(公告)日：1998-08-25
申请号：JP34176097
申请日：1997-12-11
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： YAMADA MAKOTO , ONO HIROTAKA , KANAMORI TERUHISA , OISHI YASUTAKE
IPC分类号： H01S3/07 , H01S3/06 , H01S3/10
摘要： PROBLEM TO BE SOLVED: To provide a 1.58μm optical amplifier, having a flat wide-band amplification characteristic and an optical amplifying method using the amplifier. SOLUTION: An optical fiber amplifier is provided with an erbium (Er)-doped fiber 1, which contains erbium added to at least either its core section or clad section, pumping light sources 2A and 2B which pump the fiber 1, optical means 3A and 3B which make excited light and signal light from the light sources 2A and 2B incident to the fiber 1, and optical isolators 4A and 4B. An optical fiber of 1.58μm band having an equivalent fiber length, namely, the product of the length (m) of the fiber and the concentration (wt. ppm) of the added erbium, at which the signal gain obtained at the wavelengths of the light sources 2A and 2B used for pumping the fiber 1 becomes a prescribed reference value or larger, is used as the fiber 1.

29. 发明专利

JPH09138432A OPTICAL AMPLIFIER 失效
公开(公告)号：JPH09138432A
公开(公告)日：1997-05-27
申请号：JP29565295
申请日：1995-11-14
申请人： NIPPON TELEGRAPH & TELEPHONE
发明人： YAMADA MAKOTO , ONO HIROTAKA , KANAMORI TERUHISA , OISHI YASUTAKE , SUDO SHOICHI
IPC分类号： G02F1/35 , H01S3/06 , H01S3/07 , H01S3/10
摘要： PROBLEM TO BE SOLVED: To obtain an optical fiber amplifier which is low in noise and has a broad band amplification band characteristic by connecting an optical amplifier of a first stage and an optical amplifier of the ensuing stage via an optical isolator. SOLUTION: A light source 2-1 which excites Er at a I11/2 level is used in the first-stage optical amplifier 7-1. As a result, the noises of an amplifying medium are decreased down to the quantum threshold (noise index 3dB). Both of the naturally released light which is generated in the rear-stage amplifier section 7-2 and is made incident on the fore-stage amplifier section 7-l arising when the plural amplifier sections 7-1, 7-2 are connected in series by the optical isolator 5 and the exciting light of the rear-stage amplifier section 7-2 made incident on the fore-stage amplifier section 7-1 are removed and the deterioration in the noise characteristics of the naturally released light and the exciting light of the rear-stage amplifier section 7-2 made incident on the fore-stage amplifier section 7-1 is eliminated. Namely, the lower noise of the fore-stage amplifier section 7-1 is attained by this method and, therefore, the noise characteristic over the entire part of the amplifiers is greatly improved.

30. 发明专利

JP2002270927A ASE LIGHT SOURCE 失效
公开(公告)号：JP2002270927A
公开(公告)日：2002-09-20
申请号：JP2001064046
申请日：2001-03-07
申请人： NIPPON TELEGRAPH & TELEPHONE , NTT ELECTRONICS CORP
发明人： ONO HIROTAKA , SHIMIZU MAKOTO , KANAMORI TERUHISA , AOZASA SHINICHI , OISHI YASUTAKE , NISHIDA YOSHIKI
IPC分类号： H01S3/06 , H01S3/094 , H01S3/10
摘要： PROBLEM TO BE SOLVED: To provide an ASE light source that can obtain high outputs over a wide wavelength range in the vicinity of 1,470 nm. SOLUTION: This ASE light source uses a Tm-doped optical fiber 1 and two kinds of excitation light rays of first excitation light corresponding to the energy of Tm ions between H6 and F4 levels and second excitation light corresponding to the energy of Tm ions between F4 and H4 levels. First and second multiplexers 2-1 and 2-2 are connected between a first excitation light source 3-1 which generates the first exciting light and the Tm-doped optical fiber 1 and between a second excitation light source 3-2 which generates the second excitation light and the first multiplexer 2-1, respectively. Preferably, a reflecting mirror module 5 or an optical terminator is provided at one end of the optical fiber 1. Consequently, this light source can obtain high outputs over a wide frequency range in the vicinity of 1,470 nm, because electrons at the base level H6 can be made to be involved in light emission by efficiently exciting the electrons to the light emitting level H4 .

你已经成功收藏专利！

检索式保存成功!

IPRDB

热门服务

关于我们

友情链接

联系方式