-
公开(公告)号：US6055044A
公开(公告)日：2000-04-25
申请号：US106298
申请日：1998-06-29
申请人： Haruyoshi Uchiyama , Zhixien Lee
发明人： Haruyoshi Uchiyama , Zhixien Lee
CPC分类号： G01M11/3172
摘要： There is provided an apparatus for measuring the characteristics of an optical fiber in which a frequency difference between first and second coherent light respectively generated by first and second light sources can be accurately set and wherein preferable coherent detection can be carried out in accordance with frequency components of returned light. First coherent light at a frequency f1 is converted into a pulse light which is output to the optical fiber to be measured. The characteristics of the optical fiber are measured by multiplexing returned light from the optical fiber to be measured and second coherent light at a frequency f2 and by detecting the multiplexed light. A component .vertline.f1-f2.vertline. is detected from an optical signal obtained by the multiplexed light and is mixed with a signal at a frequency fr to decrease the frequency. An electric signal at a voltage level corresponding to a differential frequency .vertline.f1-f2.vertline.-fr included in the mixed signal is generated, and a predetermined voltage level is generated which corresponds to a set value for an optical frequency difference between the first and second coherent light. The second light source is driven based on the difference between the two voltage levels to correct the frequency of the second coherent light.
摘要翻译： 提供了一种用于测量光纤的特性的装置，其中可以精确地设置分别由第一和第二光源产生的第一和第二相干光之间的频率差，并且可以根据频率分量进行优选的相干检测 的返回光。 频率为f1的第一相干光被转换为输出到要测量的光纤的脉冲光。 光纤的特性通过将来自被测光纤的返回光和频率f2的第二相干光复用，并通过检测多路复用光来测量。 分量| f1-f2 | 从由复用光获得的光信号中检测出，并以频率fr与信号混合以降低频率。 产生与包含在混合信号中的差分频率| f1-f2 | -fr相对应的电压电平的电信号，并且产生与第一和第二信号之间的光频差的设定值相对应的预定电压电平 相干光。 基于两个电压电平之间的差来驱动第二光源，以校正第二相干光的频率。
-
公开(公告)号：US5880824A
公开(公告)日：1999-03-09
申请号：US924325
申请日：1997-09-05
CPC分类号： G01L1/242 , G01D5/344 , G01D5/35358
摘要： An object of the present invention is to provide an optical fiber strain measuring apparatus which can perform precise measurement without causing any fluctuation in signal level. To achieve the above object the present invention comprises: a polarization plane rotation device 105 which rotates a plane of polarization of an optical pulse; a photo-directional coupler 106 which projects an optical pulse projected from the polarization plane rotation device 105 into an optical fiber 107 to be measured, and projects out backscattering light produced in the optical fiber 107 to be measured; a polarization plane rotation device 160 which rotates a plane of polarization of a reference light; a light mixing device 109 for mixing the backscattering light projected out from the photo-directional coupler 106 and the reference light projected from the polarization plane rotation device 160; and a signal processing section 111 which detects the mixed light projected from the light mixing device 109, converts the detected light into an electrical signal and subjects the electrical signal to a predetermined operational processing to obtain a measurement waveform.
摘要翻译： 本发明的目的是提供一种可以进行精确测量而不引起信号电平波动的光纤应变测量装置。 为了实现上述目的，本发明包括：使光脉冲的偏振平面旋转的偏振面旋转装置105; 将从偏振面旋转装置105投射的光脉冲投射到被测光纤107的光定向耦合器106，投射出待测光纤107中产生的后向散射光; 旋转参考光的偏振平面的偏振面旋转装置160; 用于混合从光定向耦合器106射出的后向散射光和从偏振面旋转装置160投影的参考光的光混合装置109; 以及信号处理部111，其检测从光混合装置109射出的混合光，将检测出的光转换为电信号，并对电信号进行预定的运算处理，得到测定波形。
-
公开(公告)号：US5880463A
公开(公告)日：1999-03-09
申请号：US954799
申请日：1997-10-21
申请人： Haruyoshi Uchiyama
发明人： Haruyoshi Uchiyama
CPC分类号： G01M11/39 , G01B11/18 , G01D5/35364 , G01L1/242
摘要： The objective of the present invention is to offer an optical fiber strain-measuring apparatus, which allows the detecting of the amount of strain at an arbitrary distance within a test optical fiber as well as the distance strain distribution, and facilitates the detecting of the back scattered light. In order to achieve the above objective, the present invention comprises an acousto-optic switch 108 which outputs a measuring pulse light, an optical circulator 112 which forwards the measuring pulse light to an optical ring circuit possessing a test optical fiber 124, while allowing the natural Brillouin back scattered light generated from the test optical fiber 124 to travel through the optical ring circuit, a frequency conversion section 132 to successively convert the reference light outputted from an optical directional coupler 102 into a reference pulse train which has its frequency change into a step form, and an acousto-optic switch 134 to output the reference pulse train as a sampling pulse, and the sampling pulse and the natural Brillouin back scattered light outputted from the optical ring circuit are converted into electrical signals by the opto-electric conversion section 138, and the signal processing section 146 measures the strain of the test optical fiber 124 based on these electrical signals.
摘要翻译： 本发明的目的是提供一种光纤应变测量装置，其能够检测测试光纤内的任意距离处的应变量以及距离应变分布，并且便于检测背面 散光 为了实现上述目的，本发明包括输出测量脉冲光的声光开关108，将测量脉冲光转发到具有测试光纤124的光环电路的光环行器112，同时允许 从测试光纤124产生的自然布里渊背散射光穿过光环电路，频率转换部分132将从光学定向耦合器102输出的参考光连续地转换成具有频率变化的参考脉冲串 步进形式和声光开关134，以输出参考脉冲串作为采样脉冲，并且从光环电路输出的采样脉冲和自然布里渊背散射光被光电转换部分转换成电信号 138，信号处理部146基于测量光纤124的应变 这些电信号。
-
公开(公告)号：US5821426A
公开(公告)日：1998-10-13
申请号：US926577
申请日：1997-09-04
申请人： Haruyoshi Uchiyama
发明人： Haruyoshi Uchiyama
CPC分类号： G01M11/39 , G01D5/35364 , G01L1/242
摘要： The objective of the present invention is to offer an optical fiber strain-measuring apparatus, which allows the measurement of the strain at an arbitrary position within an optical fiber. An optical frequency conversion section 3 shifts, in a step-wise manner for prescribed frequencies, the frequencies of a continuous light emitted from a light source 1. A sound-light switch 4 coverts into pulses the continuous light forwarded from the optical frequency conversion section 3. When those light pulses are entered into a test optical fiber, back-scattered light is generated. An optical directional coupler 11 branches and forwards to an optical ring circuit and to an optical directional coupler 13 the back-scattered light. A photo-electric converter 14 receives employing heterodyne detection and converts into electric signals the synthesized light signals of the back-scattered light forwarded from the optical directional coupler 11 and the continuous light forwarded from the optical directional coupler 2. A signal processing section 18 reads at an arbitrary timing the electric signals, performs necessary processes, and obtains the amount of strain of the test optical fiber 7.
摘要翻译： 本发明的目的是提供一种光纤应变测量装置，其允许测量光纤内的任意位置处的应变。 光频变换部分3以规定频率逐步地移动从光源1发射的连续光的频率。声光开关4将从光频变换部分转发的连续光遮盖成脉冲， 当这些光脉冲进入测试光纤时，产生背散射光。 光学定向耦合器11向光环路电路和光定向耦合器13分支并向前散射光。 光电转换器14接收采用外差检测，并将从光学定向耦合器11转发的反向散射光的合成光信号和从光学定向耦合器2转发的连续光转换成电信号。信号处理部分18读取 在任意定时，电信号执行必要的处理，并获得测试光纤7的应变量。
-
5.发明授权
公开(公告)号：US5781322A
公开(公告)日：1998-07-14
申请号：US696074
申请日：1996-08-13
申请人： Haruyoshi Uchiyama , Zhixien Li , Kazuo Aida
发明人： Haruyoshi Uchiyama , Zhixien Li , Kazuo Aida
CPC分类号： G01J11/00
摘要： An optical pulse signal produced by modulating a continuous laser light by means of a first pulse having a period sufficiently shorter than the atomic lifetime in the upper energy state of a rare earth doped fiber is input to an optical amplifier to be measured, while an output signal from the optical amplifier is modulated by a second pulse synchronized with the first pulse and having a phase difference relative to the first pulse which can be optionally set so that rapid phase adjustment relative to the first pulse is possible based on the phase at the time of minimum optical power. The noise figure of the optical amplifier is then measured based on, the maximum photoelectric power (P.sub.AMP +P.sub.ASE) and the minimum photoelectric power P.sub.ASE of the resultant optical signal.
摘要翻译： 通过在稀土掺杂光纤的上能量状态下通过具有比原子寿命充分短的时间的第一脉冲调制连续激光而产生的光脉冲信号被输入到待测量的光放大器，而输出 来自光放大器的信号由与第一脉冲同步的第二脉冲调制，并具有相对于第一脉冲的相位差，该第一脉冲可以可选地被设置为使得可以基于当时的相位相对于第一脉冲进行快速相位调整 的最小光功率。 然后，基于最终的光信号的最大光电功率（PAMP + PASE）和最小光电功率PASE来测量光放大器的噪声系数。
-
公开(公告)号：US5581389A
公开(公告)日：1996-12-03
申请号：US364204
申请日：1994-12-27
申请人： Tekken Lee , Nobunari Takeuchi , Haruyoshi Uchiyama , Kaoru Shimizu , Tsuneo Horiguchi , Yahei Koyamada
发明人： Tekken Lee , Nobunari Takeuchi , Haruyoshi Uchiyama , Kaoru Shimizu , Tsuneo Horiguchi , Yahei Koyamada
CPC分类号： H04B10/2572 , H01S3/1301 , H01S3/10
摘要： The present invention provides light frequency control apparatus comprising a light pulse signal generating mechanism for generating a light pulse signal of a standard frequency; a light frequency shifting mechanism for circulating this light pulse signal a predetermined number of times, delaying this light pulse signal at each cycle thereby sequentially shifting and outputting the aforementioned light pulse signal; an extracting mechanism for extracting a light pulse signal in the second half of a cycle from the output of the light frequency shifting mechanism; and a polarization control mechanism inserted into the light frequency shifting mechanism for controlling the angle of polarization of the light pulse signal circulating in the light frequency shifting mechanism based on the amount of attenuation of the light pulse signal outputted by the extracting mechanism.
摘要翻译： 本发明提供一种光频控制装置，其包括用于产生标准频率的光脉冲信号的光脉冲信号发生机构; 用于使该光脉冲信号循环预定次数的光频移位机构，在每个周期延迟该光脉冲信号，从而依次移位并输出上述光脉冲信号; 提取机构，用于从光频移位机构的输出端提取周期的后半部分的光脉冲信号; 以及偏振控制机构，其插入到所述光频移动机构中，用于基于由所述提取机构输出的所述光脉冲信号的衰减量来控制在所述光频移动机构中循环的所述光脉冲信号的偏振角。
-
7.发明授权
公开(公告)号：US5561551A
公开(公告)日：1996-10-01
申请号：US542737
申请日：1995-10-13
申请人： Takashi Iwasaki , Haruyoshi Uchiyama , Kazuo Aida , Yoshiaki Sato
发明人： Takashi Iwasaki , Haruyoshi Uchiyama , Kazuo Aida , Yoshiaki Sato
CPC分类号： H04B10/0731 , H01S3/06754 , H04B10/07 , H01S2301/02
摘要： A simple, quick and precise method for determining a noise factor of an optical amplifier system is presented and demonstrated with an apparatus based on rare-earth doped optical fibers. The method is based on rapid adjustments of the phase differentials between the input optical signals into and the output optical signals from the optical amplifier to compensate for system variables including the optical fiber lengths within the apparatus as well as in the ancillary devices. A cw laser source is modulated with a first pulse having a significantly shorter cycle than a lifetime of excited atoms within the doped fiber, and the modulated pulses are continually applied to the noise determining apparatus. The optical output signal from the apparatus is synchronized with the first pulse and the optical output signal is further modulated with a series of second pulses having increasing phase differentials in relation to the first pulse. The electrical output power from the noise determining apparatus undergoes a maximum and a minimum values, and the noise factor of the apparatus is calculated by using the values of the respective maximum and the minimum electrical output power.
摘要翻译： 介绍了一种用于确定光放大器系统的噪声系数的简单，快速和精确的方法，并用基于稀土掺杂光纤的设备进行了演示。 该方法基于输入光信号之间的相位差的快速调整和来自光放大器的输出光信号的补偿，以补偿包括装置内和辅助装置中的光纤长度的系统变量。 cw激光源通过第一脉冲进行调制，该第一脉冲具有比掺杂光纤内的激发原子的寿命显着更短的周期，并且调制脉冲被连续施加到噪声确定装置。 来自装置的光输出信号与第一脉冲同步，并且光输出信号通过相对于第一脉冲具有增加的相位差的一系列第二脉冲进一步调制。 来自噪声判定装置的电力输出功率经历最大值和最小值，并且通过使用相应的最大和最小电力输出功率的值来计算装置的噪声系数。
-
8.发明授权公开(公告)号：US06366348B1
公开(公告)日：2002-04-02
申请号：US09551448
申请日：2000-04-18
IPC分类号： G01N2188
CPC分类号： G01M11/319
摘要： The present invention provides an optical fiber distortion measuring apparatus and optical fiber distortion measuring method which make it possible to measure the amount of distortion of an optical fiber efficiently and in a short period of time. The time change waveform when a light pulse having a frequency of &ngr;1 is applied is compared with initial data (the time change waveform obtained in a case in which there is no distortion). Then, the light intensity L1 at a position Dx at which the light intensities do not agree is obtained. Next, the time change waveform is measured when a light pulse having a frequency of &ngr;2 is applied, and the light intensity L2 at position Dx is obtained. After this, the loss (resulting from distortion) in light intensities L1 and L2 is corrected, and light intensities LC1 and LC2 are obtained. Curve calculating unit 17 obtains a second-order curve which is a curve resulting from the parallel movement of a curve approximating the spectrum waveform of the initial data, and which contains the (&ngr;1, LC1) and (&ngr;2, LC2) described above. The peak frequency detecting unit 12 obtains the light frequency exhibiting a maximum value in the light intensity in the second-order curve. The distortion amount calculating unit 13 calculates the amount of distortion based on this light frequency.
摘要翻译： 本发明提供一种光纤失真测量装置和光纤失真测量方法，其可以在短时间内有效地测量光纤的失真量。 将施加了频率为ngr的光脉冲的时间变化波形与初始数据（在没有失真的情况下获得的时间变化波形）进行比较。 然后，获得光强度不一致的位置Dx处的光强度L1。 接下来，当施加具有频率为＆ngr.2的光脉冲时测量时变波形，并且获得位置Dx处的光强度L2。 之后，校正亮度L1和L2中的损失（由失真引起的），并且获得光强度LC1和LC2。 曲线计算单元17获得二阶曲线，其是由与初始数据的频谱波形近似的曲线并行运动产生的曲线，并且包含（＆ngr; 1，LC1）和（＆ngr; 2，LC2） 如上所述。 峰值频率检测单元12获得在二阶曲线中呈现出光强度的最大值的光频率。 失真量计算单元13基于该光频率来计算失真量。
-
公开(公告)号：US5949533A
公开(公告)日：1999-09-07
申请号：US102316
申请日：1998-06-22
申请人： Zhixien Lee , Haruyoshi Uchiyama
发明人： Zhixien Lee , Haruyoshi Uchiyama
CPC分类号： G01D5/35303
摘要： An optical fiber distortion measurement system (i.e., device and method) measures an optical fiber, which is constructed by alternately connecting two kinds of optical fibers whose Brillouin frequency shifts are different from each other. The system sequentially supplies optical pulses to the measured optical fiber while changing their light frequencies, so that Brillouin backscattering beams are output from the measured optical fiber. At first, the system supplies an optical pulse having a prescribed light frequency to the measured optical fiber of a non-distortion state, so that the device produces initial data representing time-related variations of light intensity of Brillouin backscattering light output from the measured optical fiber. Then, the system measures a time-related variation waveform representing light intensity of Brillouin backscattering light, which is output from the measured optical fiber supplied with the optical pulse of the prescribed light frequency. By comparing the measured time-related variation waveform with the initial data, the system determines occurrence of distortion in the measured optical fiber. Thereafter, the system discriminates a kind of the distortion, which corresponds to expansion or contraction, on the basis of a relationship between Brillouin frequency shifts, which are respectively calculated with respect to a detection point and its adjacent point on the measured time-related variation waveform. The Brillouin frequency shift is calculated in accordance with a quadratic approximation formula, which is created on the basis of the initial data.
摘要翻译： 光纤失真测量系统（即，装置和方法）测量通过交替连接布里渊频移彼此不同的两种光纤构成的光纤。 系统在改变其光频率的同时向所测量的光纤顺序地提供光脉冲，从而从所测量的光纤输出布里渊后向散射光束。 首先，系统向所测量的光纤提供具有规定的光频率的光脉冲为非失真状态，使得该器件产生表示从所测量的光学器件输出的布里渊后向散射光的光强度的时间相关变化的初始数据 纤维。 然后，系统测量表示由提供有规定光频的光脉冲的测量光纤输出的布里渊后向散射光的光强度的时间相关变化波形。 通过将测量的时间相关变化波形与初始数据进行比较，系统确定测量的光纤中的失真的发生。 此后，系统基于布里渊频移与测量时间相关变化相对于检测点和其相邻点计算的布里渊频移之间的关系来区分对应于扩张或收缩的失真的种类 波形 根据基于初始数据创建的二次近似公式计算布里渊频移。
-
公开(公告)号：US5777727A
公开(公告)日：1998-07-07
申请号：US864446
申请日：1997-05-28
申请人： Yasushi Sato , Haruyoshi Uchiyama
发明人： Yasushi Sato , Haruyoshi Uchiyama
CPC分类号： G01J11/00
摘要： An OTDR measurement device employs optical heterodyne wave detection to perform measurement on optical fibers. Optical pulses are incident on a measuring optical fiber, which in turn outputs backward scattering light. The device performs heterodyne wave detection on the backward scattering light as well as probe light whose frequency is set in proximity to a frequency of the backward scattering light, thus producing a detection voltage. The device provides a differential amplifier which performs amplification on a difference between the detection voltage and a reference voltage to produce a difference signal. An A/D converter converts the difference signal to a digital signal. Square addition is performed on the digital signal to produce a mean square signal representing property of the measuring optical fiber. Herein, calculations are performed on the mean square signal to produce a reference signal, which is then converted to the reference voltage. Herein, the reference signal is produced based on a reference value which is determined in advance such that the difference signal corresponds to an intermediate value of a voltage conversion range of the A/D converter under a state where only the probe light is incident on the device. Moreover, the reference signal is automatically changed to correct a shift of the reference voltage due to disturbance factors such as variations of temperature.
摘要翻译： OTDR测量装置采用光外差波检测来对光纤进行测量。 光脉冲入射到测量光纤上，测量光纤又输出反向散射光。 该装置对后向散射光进行外差波检测以及将频率设定在靠近反向散射光的频率的探测光，从而产生检测电压。 该器件提供了一种差分放大器，其对检测电压和参考电压之间的差进行放大以产生差分信号。 A / D转换器将差分信号转换成数字信号。 对数字信号进行平方加法，以产生表示测量光纤特性的均方根信号。 这里，对均方根信号进行计算以产生参考信号，然后将其转换为参考电压。 这里，参考信号是基于预先确定的参考值产生的，使得差分信号对应于在只有探测光入射到其上的A / D转换器的电压转换范围的中间值 设备。 此外，参考信号被自动改变以校正由于诸如温度变化的干扰因素引起的参考电压的偏移。
-
-
-
-
-
-
-
-
-
搜索结果
17 条记录 (耗时 0.013 秒)
