公开(公告)号：US06549711B1

公开(公告)日：2003-04-15

申请号：US09240593

申请日：1999-02-01

申请人： Tadakatsu Shimada ,  Kazuo Koya ,  Noboru Edagawa ,  Masatoshi Suzuki ,  Itsuro Morita

发明人： Tadakatsu Shimada ,  Kazuo Koya ,  Noboru Edagawa ,  Masatoshi Suzuki ,  Itsuro Morita

IPC分类号： G02B602

CPC分类号： G02B6/02247 ,  C03B37/027 ,  C03B2203/06 ,  C03B2203/18 ,  C03B2203/36 ,  G02B6/02 ,  G02B6/02028

摘要： The soliton pulse compression optical fiber comprises a core and a clad that surrounds the core for compressing the injected light pulse in width. The maximum relative index difference between the core and the clad is between about 1.2% and 2.5%. The core diameter of the soliton pulse compression optical fiber varies along the length of the soliton pulse compression optical fiber and the core has a step-like refractive index distribution. The optical fiber perform of the soliton pulse compression optical fiber comprises a core preform, which is to be a core of the soliton pulse compression optical fiber, and a clad preform that surrounds the core preform. The maximum relative index difference between the core perform and the clad preform is also between about 1.2% and 2.5%.

摘要翻译： 孤子脉冲压缩光纤包括芯和围绕芯的包层，用于压缩注入的光脉冲的宽度。 芯和包层之间的最大相对折射率差在约1.2％至2.5％之间。 孤子脉冲压缩光纤的芯直径沿着孤子脉冲压缩光纤的长度变化，并且芯具有阶梯状折射率分布。 孤子脉冲压缩光纤的光纤执行包括作为孤子脉冲压缩光纤的核心的芯预制棒和围绕芯预制棒的包层预制棒。 核心执行和包层预制件之间的最大相对折射率差异也在约1.2％至2.5％之间。

公开(公告)号：US06445478B1

公开(公告)日：2002-09-03

申请号：US09764271

申请日：2001-01-19

申请人： Katsuhiro Shimizu ,  Takashi Mizuochi ,  Takeshi Komiya ,  Kiwami Matsushita ,  Tadayoshi Kitayama ,  Masatoshi Suzuki ,  Hidenori Taga ,  Shu Yamamoto ,  Noboru Edagawa ,  Itsuro Morita

发明人： Katsuhiro Shimizu ,  Takashi Mizuochi ,  Takeshi Komiya ,  Kiwami Matsushita ,  Tadayoshi Kitayama ,  Masatoshi Suzuki ,  Hidenori Taga ,  Shu Yamamoto ,  Noboru Edagawa ,  Itsuro Morita

IPC分类号： H04B1004

摘要： Detection of an optical pulse position uses an optical pulse string with a determined repetitive ratio and an electric clock signal with a same frequency as the repetitive ratio of the optical pulse string. A phase of the electric clock signal oscillator is shifted and supplied to an optical modulator. The optical modulator modulates the optical pulse string based on the electric clock signal and outputs a modulated optical signal. A photo detector converts the modulated optical signal output from the optical modulator to an electric signal. The phase shift amount of the electric clock signal is controlled to maximize an output from the photo detector. Additionally, a dither signal may be used in the control of the phase shift, more than the optical modulator may be employed, and/or more than color light source may be employed. The use of at least one of feed forward and feedback control provided by maximizing an output of the photo detector allows an optical pulse having a short width to be realized.

公开(公告)号：US5629795A

公开(公告)日：1997-05-13

申请号：US521973

申请日：1995-08-31

申请人： Masatoshi Suzuki ,  Itsuro Morita ,  Shu Yamamoto ,  Noboru Edagawa ,  Hidenori Taga ,  Shigeyuki Akiba

发明人： Masatoshi Suzuki ,  Itsuro Morita ,  Shu Yamamoto ,  Noboru Edagawa ,  Hidenori Taga ,  Shigeyuki Akiba

IPC分类号： H04B10/2507 ,  H04B10/2525 ,  H04B10/29 ,  H04B10/291 ,  H01S3/00 ,  H04B10/02

CPC分类号： H04B10/25253

摘要： An optical amplifying-repeating transmission system is disclosed which is composed of an optical fiber for transmitting a lightwave signal with digital information added to return-to-zero lightwave pulses and a plurality of optical amplifying repeaters inserted in the optical fiber for transmission use. The mean value of wavelengths at which the wavelength dispersion of the optical fiber is zero is smaller than the wavelength of the lightwave signal which is transmitted over the system. The accumulated wavelength dispersion value of the optical fiber tends to increase with the distance of transmission, from a macroscopic viewpoint. The optical fiber for transmission is divided into a plurality of sections. In accordance with the accumulated wavelength dispersion value of the optical fiber in each section except at least the last one, a wavelength dispersion medium, which locally changes the wavelength dispersion in a manner to cancel the accumulated wavelength dispersion in the section at the wavelength of the lightwave signal, is inserted in the section to eliminate the accumulation of the timing jitter.

摘要翻译： 公开了一种光放大重复传输系统，其由用于传输光波信号的光纤与添加到归零光波脉冲的数字信息以及插入光纤中的多个光放大中继器组成，用于传输使用。 光纤的波长色散为零的波长的平均值小于在系统上传输的光波信号的波长。 从宏观的观点来看，光纤的累积波长色散值随着透射距离而增加。 用于传输的光纤被分成多个部分。 根据除了至少最后一个部分之外的每个部分中的光纤的累积波长色散值，波长色散介质以局部改变波长色散的方式来消除在波长的波长处的部分中的累积波长色散 光波信号，插入该部分以消除定时抖动的累积。

公开(公告)号：US06236488B1

公开(公告)日：2001-05-22

申请号：US09052072

申请日：1998-03-31

申请人： Katsuhiro Shimizu ,  Takashi Mizuochi ,  Takeshi Komiya ,  Kiwami Matsushita ,  Tadayoshi Kitayama ,  Masatoshi Suzuki ,  Hidenori Taga ,  Shu Yamamoto ,  Noboru Edagawa ,  Itsuro Morita

发明人： Katsuhiro Shimizu ,  Takashi Mizuochi ,  Takeshi Komiya ,  Kiwami Matsushita ,  Tadayoshi Kitayama ,  Masatoshi Suzuki ,  Hidenori Taga ,  Shu Yamamoto ,  Noboru Edagawa ,  Itsuro Morita

IPC分类号： H04B1004

CPC分类号： G02F1/0327 ,  G01J11/00 ,  G02F2203/26 ,  H04J14/08

摘要： Detection of an optical pulse position uses an optical pulse string with a determined repetitive ratio and an electric clock signal with a same frequency as the repetitive ratio of the optical pulse string. A phase of the electric clock signal oscillator is shifted and supplied to an optical modulator. The optical modulator modulates the optical pulse string based on the electric clock signal and outputs a modulated optical signal. A photo detector converts the modulated optical signal output from the optical modulator to an electric signal. The phase shift amount of the electric clock signal is controlled to maximize an output from the photo detector. Additionally, a dither signal may be used in the control of the phase shift, more than the optical modulator may be employed, and/or more than color light source may be employed. The use of at least one of feed forward and feedback control provided by maximizing an output of the photo detector allows an optical pulse having a short width to be realized.

摘要翻译： 光脉冲位置的检测使用具有确定的重复比率的光脉冲串和具有与光脉冲串的重复比相同频率的电时钟信号。 电时钟信号振荡器的相位移位并提供给光调制器。 光调制器基于电时钟信号调制光脉冲串，并输出调制光信号。 光检测器将从光调制器输出的调制光信号转换为电信号。 控制电时钟信号的相移量使光检测器的输出最大化。 另外，抖动信号可以用于相移的控制，可以采用多于光调制器，和/或多于彩色光源。 使用通过使光检测器的输出最大化而提供的前馈和反馈控制中的至少一个允许实现具有短宽度的光脉冲。

公开(公告)号：US5898714A

公开(公告)日：1999-04-27

申请号：US783589

申请日：1997-01-13

申请人： Itsuro Morita ,  Noboru Edagawa ,  Masatoshi Suzuki ,  Shu Yamamoto ,  Shigeyuki Akiba

发明人： Itsuro Morita ,  Noboru Edagawa ,  Masatoshi Suzuki ,  Shu Yamamoto ,  Shigeyuki Akiba

IPC分类号： G02F1/35 ,  H01S3/30 ,  H04B10/2507 ,  H04B10/2525 ,  H04B10/29 ,  H04B10/293 ,  H04B10/508 ,  H04B10/524

CPC分类号： H01S3/302 ,  H01S2301/085

摘要： An optical pulse generator, capable of generating ultrashort optical pulses suitable for optical soliton transmission, includes a DFB laser 10 for continuous laser oscillation, an electroabsorbtion modulator 12 for creating a sequence of optical pulses of the pulse width 14.6 ps from optical output of the laser 10. Output from an optical modulator 12 enters into a dispersion decreasing fiber 16 via an optical isolator 14. The dispersion decreasing fiber 16 has chromatic dispersion that decreases from 13.7 ps/nm/km to 2.3 ps/nm/km with distance, and its fiber length is 15 km. Pump laser beams from pump lasers 20, 24 are introduced to the dispersion decreasing fiber 16 by optical couplers 18, 22, and the fiber 16 functions as a Raman amplifier. When the Raman gain is 2.4 dB, the pulse width is compressed from 14.6 ps to 5.8 ps, approximately, even when the power of input pulses to the dispersion decreasing fiber 16 complies with the soliton condition.

摘要翻译： 能够产生适用于光孤子传输的超短光脉冲的光脉冲发生器包括用于连续激光振荡的DFB激光器10，用于从激光器的光输出产生脉冲宽度为14.6ps的光脉冲序列的电吸收调制器12 来自光调制器12的输出经由光隔离器14进入色散减小的光纤16.色散减小光纤16具有从距离13.7ps / nm / km降低到2.3ps / nm / km的色散，并且其色散 纤维长度为15公里。 来自泵浦激光器20,24的泵浦激光束通过光耦合器18,22引入到色散减小光纤16，并且光纤16用作拉曼放大器。 当拉曼增益为2.4dB时，即使当色散减小的光纤16的输入脉冲的功率符合孤子条件时，脉冲宽度也从大约14.6ps压缩到5.8ps。

公开(公告)号：US5642215A

公开(公告)日：1997-06-24

申请号：US521952

申请日：1995-08-31

申请人： Masatoshi Suzuki ,  Itsuro Morita ,  Noboru Edagawa ,  Hidenori Taga ,  Shu Yamamoto ,  Shigeyuki Akiba

发明人： Masatoshi Suzuki ,  Itsuro Morita ,  Noboru Edagawa ,  Hidenori Taga ,  Shu Yamamoto ,  Shigeyuki Akiba

IPC分类号： G02F1/35 ,  H01S3/10 ,  H04B10/2507 ,  H04B10/508 ,  H04B10/524 ,  H04B10/58 ,  H04B10/00

CPC分类号： H04B10/25077

摘要： An optical transmission system which permits long-distance, ultrafast, high-capacity optical soliton transmission by suppressing timing jitter with simple means. In an optical transmission system which uses a transmission line composed of an optical fiber for transmitting therethrough a lightwave signal having digital information added to a return-to-zero lightwave pulse and a plurality of optical amplifying repeaters for compensating for losses by the optical fiber and in which the pulse compression effect by the nonlinear optical effect on the optical pulse and the pulse expansion effect by the dispersion effect are compensated, at least one optical band limited element which has a flat group delay characteristic near the center frequency is disposed in the transmission line at intervals of a period Z equal to the soliton period Z.sub.sol and the product, aB.sub.sol.spsb.2, of the curvature a of the product of the intensity transfer funtions of the optical band limited elements in the vicinity of the center frequency in the soliton period and the square of the full width at half maximum, B.sub.sol, of the spectrum of the lightwave pulse to be transmitted is set to a value in the range of 2.1.times.10.sup.-2 to 8.3.times.10.sup.-2.

摘要翻译： 一种光传输系统，通过简单的手段抑制定时抖动，允许长距离，超快速，高容量的光孤子传输。 在光传输系统中，使用由光纤组成的传输线通过其传输具有添加到归零光波脉冲的数字信息的光波信号和用于补偿光纤损耗的多个光放大中继器，以及 其中通过非线性光学效应对光脉冲的脉冲压缩效应和由色散效应产生的脉冲扩展效应被补偿，至少一个在中心频率附近具有平坦组延迟特性的光学带限制元件设置在透射 以等于孤子周期Zsol的周期Z的间隔和在孤子周期中的中心频率附近的光学带限制元件的强度转移功率的乘积的曲率a的乘积aBsol2，以及 要发送的光波脉冲的频谱的半峰全宽Bsol被设定为t o在2.1×10-2至8.3×10-2的范围内的值。

公开(公告)号：US5574590A

公开(公告)日：1996-11-12

申请号：US521838

申请日：1995-08-31

申请人： Noboru Edagawa ,  Masatoshi Suzuki ,  Hidenori Taga ,  Itsuro Morita ,  Shu Yamamoto ,  Shigeyuki Akiba

发明人： Noboru Edagawa ,  Masatoshi Suzuki ,  Hidenori Taga ,  Itsuro Morita ,  Shu Yamamoto ,  Shigeyuki Akiba

IPC分类号： G02F1/35 ,  H04B10/2507 ,  H04B10/2513 ,  H04B10/29 ,  H04B10/291 ,  H04B10/508 ,  H04B10/524 ,  H04B10/58 ,  H04B10/16 ,  H04B10/12

CPC分类号： H04B10/2935 ,  H04B10/25253

摘要： An optical amplifying transmission system is disclosed in which a large quantity of optical fiber whose zero dispersion wavelength is longer than the wavelength of the lightwave signal is introduced to provide an RZ lightwave signal transmission system. In this system, the average zero dispersion wavelength by the optical fiber is shorter than the wavelength of the lightwave signal, the zero dispersion wavelength by the optical fiber whose length is in the range of one-thirds to two-thirds of the entire length of the optical fiber is longer than the wavelength of the lightwave signal, and the absolute value of the wavelength dispersion is larger than one-half the absolute value of the average wavelength dispersion value over the entire length of the optical fiber.

摘要翻译： 公开了一种光放大传输系统，其中引入了零色散波长比光波信号的波长长的大量光纤，以提供RZ光波信号传输系统。 在该系统中，光纤的平均零色散波长比光波信号的波长短，其长度为全长的三分之一到三分之二的光纤的零色散波长 光纤比光波信号的波长长，波长色散的绝对值大于光纤的整个长度上的平均波长色散值的绝对值的一半。

公开(公告)号：US6005702A

公开(公告)日：1999-12-21

申请号：US802698

申请日：1997-02-19

申请人： Masatoshi Suzuki ,  Itsuro Morita ,  Noboru Edagawa ,  Shu Yamamoto ,  Shigeyuki Akiba

发明人： Masatoshi Suzuki ,  Itsuro Morita ,  Noboru Edagawa ,  Shu Yamamoto ,  Shigeyuki Akiba

IPC分类号： G02F1/01 ,  H04B10/2507 ,  H04B10/2525 ,  H04B10/508 ,  H04B10/516 ,  H04B10/524 ,  H04B10/556 ,  H04B10/58 ,  H04B10/61 ,  H04J14/00 ,  H04J14/02 ,  H04L25/02 ,  H04L25/49 ,  H04B10/04 ,  H04B10/12

CPC分类号： H04B10/505 ,  H04B10/5051 ,  H04B10/506 ,  H04B10/508 ,  H04J14/02

摘要： An optical transmission device using return-to-zero optical pulses as transmission optical pulses, which is capable of enhancing a transmission distance as well as a wavelength range with satisfactory transmission characteristics and enabling an easy realization of the wavelength division multiplexing optical transmission. The optical transmission device is formed by an optical transmitter for transmitting transmission optical pulses by superposing digital data signals onto return-to-zero optical pulses, and a modulator for applying one of a phase modulation and a frequency modulation in synchronization with a transmission rate of the transmission optical pulses, to the transmission optical pulses transmitted by the optical transmitter. This optical transmission device can be utilized in forming a wavelength division multiplexing optical transmission apparatus and an optical transmission system.

摘要翻译： 一种使用归零光脉冲作为传输光脉冲的光传输装置，其能够增强传输距离以及具有令人满意的传输特性的波长范围，并且能够容易地实现波分复用光传输。 光传输装置由光发射机形成，用于通过将数字数据信号叠加在归零光脉冲上来发送传输光脉冲;以及调制器，用于将相位调制和频率调制中的一个与传输速率 传输光脉冲，由光发送器传输的传输光脉冲。 该光传输装置可以用于形成波分复用光传输装置和光传输系统。

公开(公告)号：US5889607A

公开(公告)日：1999-03-30

申请号：US868976

申请日：1997-06-04

申请人： Masatoshi Suzuki ,  Noboru Edagawa ,  Itsuro Morita ,  Shu Yamamoto ,  Shigeyuki Akiba

发明人： Masatoshi Suzuki ,  Noboru Edagawa ,  Itsuro Morita ,  Shu Yamamoto ,  Shigeyuki Akiba

IPC分类号： G02F1/01 ,  G02F1/015 ,  G02F1/025 ,  H01S5/00 ,  G02F1/03

CPC分类号： G02F1/015 ,  G02F1/0121 ,  G02F2001/0157 ,  G02F2203/06 ,  G02F2203/26

摘要： Incident light 1 is inputted to an electro-absorption-type optical modulator 4 via an optical circulator 2 and a lens 3, and subjected to intensity modulation that corresponds to a modulation signal 8. The optical signal outputted by the electro-absorption-type optical modulator 4 is inputted to a Faraday rotator 6 via a lens 5, and the plane of polarization is rotated 45.degree.. The optical signal transmitted by the Faraday rotator 6 is totally reflected by a totally reflecting mirror 7, inputted for the second time to the Faraday rotator 6, then passed through the lens 5 after the plane of polarization has been rotated 45.degree. by this Faraday rotator 6, and readmitted by the electro-absorption-type optical modulator 4. The output of the electro-absorption-type optical modulator 4 is emitted via the lens 3 and the optical circulator 2. The polarization dependence of insertion loss can be eliminated because the plane of polarization is rotated 90.degree., and the incident light 1 readmitted to the electro-absorption-type optical modulator 4 at any plane of polarization. In view of this, the polarization dependent loss of an electro-absorption-type optical modulator can be eliminated by employing such optical modulators and creating a high-performance optical short pulse generating device, optical waveform shaping device, and optical demultiplexer.

摘要翻译： 入射光1通过光环行器2和透镜3输入到电吸收型光调制器4，经受与调制信号8对应的强度调制。由电吸收型光 调制器4通过透镜5输入到法拉第转子6，偏振面旋转45度。 由法拉第旋转器6传输的光信号被全反射镜7全反射，全反射镜7第二次输入到法拉第旋转器6，然后在该法拉第旋转器旋转了45°的偏振面之后通过透镜5 电吸收型光调制器4再次进入。电吸收型光调制器4的输出通过透镜3和光循环器2发射。插入损耗的偏振依赖性可以被消除，因为 偏振平面旋转90°，入射光1以任何偏振平面返回到电吸收型光调制器4。 鉴于此，可以通过采用这种光学调制器来消除电吸收型光学调制器的偏振相关损耗，并且产生高性能的光学短脉冲产生装置，光学波形整形装置和光学解复用器。

公开(公告)号：US5864421A

公开(公告)日：1999-01-26

申请号：US864192

申请日：1997-05-28

申请人： Masatoshi Suzuki ,  Noboru Edagawa ,  Itsuro Morita ,  Shu Yamamoto ,  Shigeyuki Akiba

发明人： Masatoshi Suzuki ,  Noboru Edagawa ,  Itsuro Morita ,  Shu Yamamoto ,  Shigeyuki Akiba

IPC分类号： G02F1/35 ,  G02F1/33 ,  G02F2/02 ,  H04B10/2507 ,  H04B10/2519 ,  H04B10/2525 ,  H04B10/2569 ,  H04B10/29 ,  H04B10/291 ,  H04B10/02

CPC分类号： H04B10/25077 ,  G02F1/33

摘要： An optical frequency shifter which has no insertion loss polarization dependency and no polarization mode dispersion is formed by: at least one ultrasonic wave generator for generating ultrasonic waves; at least one electric acousto-optic element forming at least one diffraction grating therein upon being applied with the ultrasonic waves generated by the ultrasonic wave generator; at least one polarization rotator for rotating a polarization plane of a first primary diffracted light produced by the diffraction grating, by 90.degree.; and a light path through which an input light is entered into the electric acousto-optic element at a Bragg angle of the diffraction grating in a prescribed direction side, the prescribed direction being defined as either identical or opposite to a propagation direction of the ultrasonic waves, so that the first primary diffracted light is produced by the diffraction grating from the input light, a polarization plane rotated light produced by the polarization rotator is entered into the electric acousto-optic element at a Bragg angle of the diffraction grating in the prescribed direction side, and a second primary diffracted light produced by the diffraction grating from the polarization plane rotated light is outputted as an output light. An optical soliton-like return-to-zero pulse transmission system using a combination of this optical frequency shifter and a fixed optical filter in an optical amplifier repeater is also disclosed.

摘要翻译： 通过以下方法形成没有插入损耗极化依赖性和无偏振模色散的光学移频器：至少一个用于产生超声波的超声波发生器; 至少一个电声光学元件在被施加超声波发生器产生的超声波时形成至少一个衍射光栅; 至少一个偏振旋转器，用于将由衍射光栅产生的第一主衍射光的偏振面旋转90度; 以及在规定的方向侧以衍射光栅的布拉格角将输入光输入到电声元件中的光路，规定的方向被定义为与超声波的传播方向相同或相反 ，使得第一主衍射光由衍射光栅从输入光产生，由偏振旋转器产生的偏振面旋转的光以预定方向的衍射光栅的布拉格角进入电声元件 输出由衍射光栅从偏振面旋转的光产生的第二主衍射光作为输出光。 还公开了在光放大器中继器中使用该光移频器和固定滤光器的组合的光孤子状归零脉冲传输系统。