摘要:
High peak pulse light is incident on an optical fiber having a dispersion decreasing region which serves as a main region for generating supercontinuum or idler light and in which the chromatic dispersion does not increase but at least partially decreases in the direction in which light travels. The fiber can be applied to broad band width idler light generation with both light transmission directions. Four wave mixing upon incidence of the light on the dispersion decreasing region of the optical fiber are efficiently obtained.
摘要:
The present invention relates to an optical transmission system and a channel assigning method with structure to reduce dispersion of power levels among signals dropped at respective signal branchpoints on an optical transmission line out of signals of multiple channels amplified in an optical amplifier. The optical transmission system has an optical transmission line in which signals of multiple channels propagate, an optical amplifier provided on the transmission line, and a plurality of signal branchpoints disposed on the downstream transmission line in which the signals of the channels outputted from the optical amplifier propagate. Each of the signal branchpoints drops a signal of a channel with a lowest power level out of arriving signals in the channels. This reduces the dispersion of power levels among signals dropped at the respective branchpoints, as a whole of the optical transmission system.
摘要:
Disclosed are an optical transmission system and a Raman amplifying control unit that can stabilize the effective loss of a transmission line even if the optical transmission system has a relay station between a transmitting station and a receiving station. The optical transmission system and the Raman amplifying control unit have an introducing means for outputting inspection light and introducing it to the transmission line, a receiving means for receiving the back-scatter from the inspection light, and a control means for inspecting the transmission line and controlling an exciting light supplying means according to the received backscattering light. The introducing means, the receiving means, and the control means are provided together with the exciting light supplying means in a station at the transmitting side or receiving side of a relay section in the optical transmission system.
摘要:
The present invention relates to a nonlinear optical fiber which can generate a nonlinear optical phenomenon with high efficiency, an optical fiber coil wound with the nonlinear optical fiber, and a wavelength converter equipped with the nonlinear optical fiber. In particular, the nonlinear optical fiber according to the present invention has, as characteristics with respect to input light having a predetermined wavelength, a mode field diameter of 5 &mgr;m or less, a polarization mode dispersion of 1 ps/km½ or less or a fixed plane of polarization, a zero-dispersion wavelength of not less than 1.5 &mgr;m but not greater than 1.6 &mgr;m, a cutoff wavelength of not less than 1.4 &mgr;m but not greater than 1.7 &mgr;m at a length of 2 m, a transmission loss of 3 dB/km or less, and a nonlinear coefficient of 10/W/km or more. As a result of this configuration, the nonlinear optical fiber generates, with high efficiency, desirable converted light occurring upon the nonlinear phenomenon.
摘要翻译:本发明涉及一种能够高效率地产生非线性光学现象的非线性光纤,与非线性光纤缠绕的光纤线圈以及配备非线性光纤的波长转换器。 特别地,根据本发明的非线性光纤作为具有预定波长的输入光的特性,模场直径为5um以下,偏振模色散为1ps / km 1/2以下或固定 偏振平面,零分散波长不小于1.5μm但不大于1.6μm,截止波长不小于1.4μm,但不大于1.7μm,长度为2μm,传输损耗为3dB / km以下,非线性系数为10 / W / km以上。 作为该结构的结果,非线性光纤以非线性现象产生期望的转换光,高效率地产生。
摘要:
In an optical amplifier according to the present invention, a change signal from a change signal source is fed into a light source or a drive circuit. The wavelength of light outputted from the light source is changed based on the change signal. The wavelength-changed output light from the light source is outputted as pumping light from a pumping light generator to be supplied backwardly via an optical multiplexer/demultiplexer into an optical fiber. Signal light is Raman-amplified in the optical fiber with the supply of the pumping light.
摘要:
An optical communication system has a configuration in which an optical transmission line is laid between a repeater (transmitter) and another repeater (receiver). The optical transmission line is formed by fusion-splicing a first optical fiber on the upstream side and a second optical fiber on the downstream side. The first optical fiber has a transmission loss of 0.25 dB or less, and an effective area of 80 μm2 or above (preferably 100 μm2 or above), at a wavelength of 1550 nm, which is the wavelength of signal light. The second optical fiber is connected to the downstream end of the first optical fiber and has positive dispersion regions and negative dispersion regions which are alternately arranged along the longitudinal direction and whose chromatic dispersions at a wavelength of 1550 nm are positive and negative, respectively.
摘要:
The present invention provides a dispersion compensating system for bi-directional optical communication using wavelength division multiplexing transmission. Signal lights bi-directionally pass through a signal optical fiber which comprises a dispersion compensating fiber working bi-directionally.
摘要:
The present invention relates to an optical transmission line enabling Raman amplification of an optical signal when pumping light is supplied thereto, a method of making this optical transmission line, and an optical transmission system using this optical transmission line. This optical transmission line is an optical transmission line enabling Raman amplification of an optical signal when pumping light is supplied thereto, wherein a region yielding the maximum value of Raman gain coefficient is separated from an end portion where the pumping light is supplied by a predetermined distance along a direction in which the pumping light advances. This optical transmission line can restrain the power of optical signal, at any point of the optical transmission line, from increasing to such an extent that optical Kerr effects occurs remarkably and from decreasing to such an extent that the SN ratio deteriorates greatly, and can fully secure the power of optical signal at the end point of the optical transmission line.
摘要:
An optical signal, which is to become the subject of dispersion compensation, is split by optical combining/splitting unit 2, and each frequency component of the optical signal that is split is reflected by the corresponding reflective mirror 30 included in reflective mirror group 3 to apply a predetermined phase shift to the respective frequency components Each reflected frequency component is then combined using optical combining/splitting unit 2, to give dispersion compensated optical signal Furthermore, in regards to reflective mirror group 3, which is used to apply phase shift to each frequency component of an optical signal, each of the respective plurality of reflective mirrors 30 is made a movable mirror having a movable reflection position that reflects the frequency components. Through this, dispersion that develops in an optical signal may be compensated with favorable controllability and high accuracy. Therefore, the precision and controllability of dispersion compensation will become superior, and realized is a variable dispersion compensator having a miniaturized optical circuit, and an optical transmission system comprising such variable dispersion compensator,
摘要:
The present invention relates to an optical transmission line enabling Raman amplification of an optical signal when pumping light is supplied thereto, a method of making this optical transmission line, and an optical transmission system using this optical transmission line. This optical transmission line is an optical transmission line enabling Raman amplification of an optical signal when pumping light is supplied thereto, wherein a region yielding the maximum value of Raman gain coefficient is separated from an end portion where the pumping light is supplied by a predetermined distance along a direction in which the pumping light advances. This optical transmission line can restrain the power of optical signal, at any point of the optical transmission line, from increasing to such an extent that optical Kerr effects occurs remarkably and from decreasing to such an extent that the SN ratio deteriorates greatly, and can fully secure the power of optical signal at the end point of the optical transmission line.