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公开(公告)号：US4773759A
公开(公告)日：1988-09-27
申请号：US049805
申请日：1987-05-12
CPC分类号： G01C19/72
摘要： A fiber optic interferometer provides Kerr effect compensation by intensity modulating counterpropagating waves of unequal intensity such that the average value of the square of the intensity is equal to a constant times the average value of the intensity squared, the constant preferably being equal to about two. The intensity modulation may be achieved by using a modulator in combination with a light source or by using a source in which plural frequencies combine to provide the modulation.
摘要翻译： 光纤干涉仪通过强度调制不等强度的反向传播波提供克尔效应补偿，使得强度平方的平均值等于强度平方值的平均值的常数，该常数优选等于约2。 可以通过使用与光源组合的调制器或通过使用多个频率组合以提供调制的源来实现强度调制。
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32.发明授权System and method for accurate loop length determination in fiber-optic sensors and signal processors 失效光纤传感器和信号处理器的精确环路长度确定的系统和方法
公开(公告)号：US4768880A
公开(公告)日：1988-09-06
申请号：US877321
申请日：1986-06-23
申请人： Moshe Tur , Byoung Y. Kim , Janet L. Brooks , Herbert J. Shaw
发明人： Moshe Tur , Byoung Y. Kim , Janet L. Brooks , Herbert J. Shaw
CPC分类号： G01D5/35303
摘要： A technique and system for accurate determination of differential propagation delays in fiber-optic circuits. The method includes providing a sinusoidally modulated optical signal to each of two waveguides defining optical paths. The optical signals received from the optical paths are combined to form a reference output signal which has a null waveform whenever the propagation delay between the optical signals contains an odd number of half periods of the optical signal waveforms. The difference in the sinusoidal modulation frequency producing a first and second null or constant waveform in the reference signal is determined. This difference value between adjacent frequencies forming the null or constant waveforms comprises the inverse of the difference of signal propagation delay in the two optical paths. Accuracy is improved by measuring the sinusoidal modulation frequencies corresponding to first and second waveforms which are not formed by adjacent frequencies. The difference between those nonadjacent frequencies is divided by the difference in the reference waveform orders of the null reference waveforms to obtain the inverse of the differential propagation delay. Further accuracy is achieved by measuring at least one of the waveform nulls at a high waveform order. Still further accuracy is achieved by monitoring the reference waveforms on a network analyzer and using a frequency synthesizer to more precisely match and identify the modulation frequencies corresponding to the null reference signal waveforms. A system is disclosed for implementing this technique optionally using optical sources having a short coherence length. Mathematical relationships are disclosed for use with measured values in obtaining further improved accuracy.
摘要翻译： 一种用于精确确定光纤电路差分传播延迟的技术和系统。 该方法包括向定义光路的两个波导中的每一个提供正弦调制光信号。 每当光信号中的传播延迟包含光信号波形的奇数个半周期时，从光路接收的光信号被组合以形成具有零波形的参考输出信号。 确定在参考信号中产生第一和第二无效或恒定波形的正弦调制频率的差异。 形成零波形或恒定波形的相邻频率之间的差值包括两个光路中的信号传播延迟差的倒数。 通过测量对应于不由相邻频率形成的第一和第二波形的正弦调制频率来提高精度。 这些不相邻频率之间的差异除以空参考波形的参考波形次数的差异，以获得差分传播延迟的倒数。 通过以高波形顺序测量至少一个波形零点来实现进一步的精度。 通过监视网络分析仪上的参考波形并使用频率合成器更精确地匹配和识别与空参考信号波形相对应的调制频率，可以进一步提高精度。 公开了一种用于实现该技术的系统，其可选地使用具有短相干长度的光源。 公开了与测量值一起使用的数学关系，以获得进一步提高的准确度。
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公开(公告)号：US4768850A
公开(公告)日：1988-09-06
申请号：US622637
申请日：1984-06-20
CPC分类号： H04L25/03057 , G02B6/2861
摘要： A fibre optic lattice filter having a transfer function wherein the poles and zeros are adjustable independently of each other. The filter comprises a cascaded configuration of recursive and non-recursive fiber optic lattice filters. In one preferred embodiment, an all-pass fiber optic filter is formed by cascading all-pole and all-zero lattice filters, and by processing the resulting filtered output signal in a subtractive detection system. This detection system produces a signal which represents the difference between two signal outputs provided by the all-zero filter section, and which is adjustable in magnitude, thereby providing an overall filtering function which is capable of handling both positive and negative valued input signals.
摘要翻译： 一种具有传递函数的光纤格栅滤波器，其中极点和零点彼此独立地调节。 滤波器包括递归和非递归光纤网格滤波器的级联配置。 在一个优选实施例中，全通光纤滤波器通过级联全极点和全零点阵滤波器，并通过在减法检测系统中处理所得到的滤波输出信号来形成。 该检测系统产生一个信号，该信号表示由全零滤波器部分提供的两个信号输出之间的差异，其可在幅度上调节，从而提供能够处理正值和负值输入信号的整体滤波功能。
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公开(公告)号：US4738503A
公开(公告)日：1988-04-19
申请号：US828782
申请日：1986-02-12
CPC分类号： G02B6/24 , G02B6/2821 , G02B6/2861 , G11C21/00 , H01S3/0057 , H01S3/302 , G02F2203/54 , H01S2301/08 , Y10S359/90
摘要： A fiber optic recirculating memory comprises a splice-free length of optical fiber which forms a loop that is optically closed by means of a fiber optic coupler. The coupler couples an optical signal input pulse to the loop for circulation therein, and outputs a portion of the signal pulse on each circulation to provide a series of output pulses. A pump source is included to pump the fiber loop with a pump signal having sufficient intensity to cause stimulated Raman scattering in the fiber loop, and thereby cause amplification of the circulating signal pulse. The fiber characteristics, coupler characteristics, and a pump power are selected to yield a Raman gain which compensates for the total round-trip losses in the fiber loop, so as to provide an output pulse train of constant amplitude pulses. The invention may be implemented utilizing a standard coupler with a pump signal modulation technique. The pump signal is input to the loop as a series of pulses having a duration and a periodicity chosen to prevent overlap of recirculating pump pulses with input pump pulses until at least two circulations of the loop, which minimizes pump power fluctuations and will therefore enhance output signal stability.
摘要翻译： 光纤再循环存储器包括无接头长度的光纤，其形成通过光纤耦合器光闭合的环路。 耦合器将光信号输入脉冲耦合到环路以在其中循环，并且在每个循环上输出信号脉冲的一部分以提供一系列输出脉冲。 包括泵浦源以用具有足够强度的泵浦信号泵送光纤环，以在光纤回路中引起受激拉曼散射，从而引起循环信号脉冲的放大。 选择光纤特性，耦合器特性和泵浦功率以产生拉曼增益，其补偿光纤环路中的总往返损耗，从而提供恒定幅度脉冲的输出脉冲串。 本发明可以利用具有泵浦信号调制技术的标准耦合器来实现。 泵浦信号作为一系列具有持续时间和周期性的脉冲输入到循环中，以防止循环泵浦脉冲与输入泵浦脉冲的重叠，直到循环的至少两个循环，这最小化泵浦功率波动并且因此将增强输出 信号稳定。
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公开(公告)号：US4723827A
公开(公告)日：1988-02-09
申请号：US628650
申请日：1984-06-19
申请人： Herbert J. Shaw , John E. Bowers
发明人： Herbert J. Shaw , John E. Bowers
CPC分类号： G02B6/2826 , G02B6/283 , G02B6/2861
摘要： A single mode optical fiber switch having a base (70) and a laterally slidable top (91). The base is composed of a quartz block (70) with a slight radius of curvature along its length supporting a silicon substrate (66) having a plurality of parallel v-grooves (68). The grooves are fitted with single mode optical fiber segments (64) and lapped to create a flat coupling surface (82) extending laterally across the base. The top (91) is composed of a quartz block with a single v-groove (93) holding a segment of single-mode fiber (95). This fiber (95) is lapped to create a flat coupling surface matable with the coupling surface on the base. The base (70) and top (91) are placed together such that the top fiber (95) may be selectively slid into and out of coupling alignment with any of the fibers (64) in the base (70) to form a discretely variable delay line. A single length of fiber (121) is wrapped around the base ( 70) in helical fashion with each loop being secured in one of the v-grooves (68). By coupling the top fiber (95) with different loops of the base fibers (121), different amounts of delay can be obtained. The delay line can be used to provide variable frequency response for notch and transversal filters.
摘要翻译： PCT No.PCT / US82 / 01608 Sec。 371日期1984年6月19日 102（e）1984年6月19日PCT PCT卷号1982年11月12日PCT公布。 公开号WO84 / 02005 日期：1984年5月24日。具有基座（70）和横向滑动顶部（91）的单模光纤开关。 基座由石英块（70）组成，石英块（70）沿其长度具有微小的曲率半径，支撑具有多个平行V形槽（68）的硅衬底（66）。 凹槽配有单模光纤段（64）并重叠，以形成横向延伸穿过底座的平坦的耦合表面（82）。 顶部（91）由具有保持单模光纤（95）的单个v形槽（93）的石英块组成。 该纤维（95）被研磨以产生可与基底上的联接表面配合的平坦的联接表面。 基部（70）和顶部（91）被放置在一起，使得顶部纤维（95）可以选择性地滑入和离开与基部（70）中的任何纤维（64）的联接对准，以形成离散变量 延迟线。 单个长度的纤维（121）以螺旋方式围绕基部（70）缠绕，每个环被固定在一个V形槽（68）中。 通过将顶部纤维（95）与基础纤维（121）的不同环耦合，可以获得不同的延迟量。 延迟线可用于为陷波和横向滤波器提供可变频率响应。
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公开(公告)号：US4652079A
公开(公告)日：1987-03-24
申请号：US527163
申请日：1983-08-26
申请人： Herbert J. Shaw , Steven A. Newton
发明人： Herbert J. Shaw , Steven A. Newton
CPC分类号： G02B6/264 , G02B6/2861 , H03K3/86 , Y10S359/90
摘要： There is disclosed a high speed pulse train generator for generating a train of pulses having arbitrarily close spacing. The apparatus consists of a generator loop comprised of a fiber optic waveguide looped through a directional coupler with the output fiber serving as the input fiber for a similarly structured multiplexer loop. The lengths of the two loops are adjusted such that the time difference in the propagation times of light around the respective loops is small compared to the time of propagation around either loop. The times are adjusted to obtain any arbitrary spacing of the pulses in the output pulse train which is comprised of interleaved pulse trains resulting from each pulse input to the multiplexer loop. Also disclosed is a single loop embodiment for bidirectional data rate transformation and methods of using all the embodiments.
摘要翻译： 公开了一种高速脉冲串发生器，用于产生具有任意紧密间隔的脉冲串。 该装置包括一个发生器回路，该发生器回路包括一个通过定向耦合器环绕的光纤波导，输出光纤用作类似结构的多路复用器回路的输入光纤。 调整两个环路的长度，使得相对于各个环路周围的光的传播时间的时间差与围绕任一环路的传播时间相比较小。 调整时间以获得输出脉冲串中的脉冲的任意间隔，其由输入到多路复用器环路的每个脉冲产生的交错脉冲串组成。 还公开了用于双向数据速率变换的单回路实施例和使用所有实施例的方法。
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公开(公告)号：US4564262A
公开(公告)日：1986-01-14
申请号：US522108
申请日：1983-08-11
申请人： Herbert J. Shaw
发明人： Herbert J. Shaw
CPC分类号： G02B6/3536 , G02B6/2826 , G02B6/283 , G02B6/3594 , Y10S359/90
摘要： Apparatus and method of manufacture for coupling optical power between two strands of fiber optic material in a given direction of propagation. The coupler employs generally parallel, intersecting strands of fiber optic material having the cladding removed on one side thereof to within a few microns of the fiber cores in the region of intersection to permit light transfer between the strands.
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公开(公告)号：US4556279A
公开(公告)日：1985-12-03
申请号：US319301
申请日：1981-11-09
CPC分类号： G02B6/29332 , G02B6/2826 , G02B6/283 , G02B6/2938 , G02B6/29395
摘要： A passive, frequency selective, fiber optic multiplexer, comprises a directional coupler in which a pair of single mode optical fibers are accurately positioned to provide evanescent field coupling, typically by polishing a portion of the cladding from each of said fibers to place the respective cores of said fibers within the evanescent field of light in the other fiber. The coupling efficiency of a coupler constructed in this manner is wavelength dependent, and provides over-coupling, that is, the capability of transferring light, virtually entirely, back and forth between the fibers within the coupler. The wavelength dependent nature of the evanescent field coupling permits multiplexing, specifically between a pair of wavelengths, one of which is coupled in its entirety from a first fiber to a second fiber, and the other of which is essentially uncoupled. By increasing the number of total transfers of the light signals between the pair of fibers, the frequency resolution of the multiplexer may be optimized for light signals of virtually any frequency separation.
摘要翻译： 无源频率选择性光纤多路复用器包括定向耦合器，其中一对单模光纤被精确地定位以提供渐逝场耦合，通常通过从每个所述光纤抛光一部分包层以放置相应的芯 的纤维在另一纤维中的消逝光场内。 以这种方式构造的耦合器的耦合效率是波长相关的，并且提供过耦合，即在耦合器内的光纤之间实际上完全传输光的能力。 消逝场耦合的波长依赖性允许多路复用，特别是在一对波长之间进行多路复用，其中一个波长的整体由第一光纤耦合到第二光纤，另一个基本上是耦合的。 通过增加一对光纤之间的光信号的总传输次数，多路复用器的频率分辨率可以针对几乎任何频率间隔的光信号进行优化。
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公开(公告)号：US4553238A
公开(公告)日：1985-11-12
申请号：US537493
申请日：1983-09-30
IPC分类号： G02B6/00 , G02B6/28 , G02B6/287 , G02F1/35 , H01S3/06 , H01S3/07 , H01S3/091 , H01S3/0915 , H01S3/094 , H01S3/30
CPC分类号： H01S3/094003 , H01S3/094011 , H01S3/094019 , H01S3/094069
摘要： A pair of small diameter optical fibers are arranged in a side-by-side configuration, the first fiber providing a passive guide for pump light, and the second fiber formed of a material, such as Nd:YAG which has amplifying properties at the signal frequency. The signal to be amplified propagates through the second fiber from the active material, resulting in amplification of the signal. The first fiber is pumped from one or both ends, utilizing a cone shaped rod which is optically coupled thereto. A large diameter beam of collimated pump light enters the cone shaped rod, where total internal reflections on the cone walls compress the beam to a small, fiber-size diameter for absorption by the active fiber. The light input to the cone-shaped rod is produced by plural, high power laser diodes, and is collimated by microlenses. By utilizing the cone-shaped rod to couple light from the high power diode lasers to the pump fiber, high pump power densities can be achieved, yielding increased amplification.
摘要翻译： 一对小直径光纤配置成并排配置，第一光纤提供泵浦光的被动导向器，第二光纤由诸如Nd：YAG的材料形成，该材料在信号处具有放大特性 频率。 要被放大的信号通过第二光纤从活性材料传播，导致信号的放大。 第一纤维从一端或两端泵送，利用光学耦合到其上的锥形杆。 准直泵浦光的大直径光束进入锥形棒，锥形壁上的全部内部反射将光束压缩至较小的纤维尺寸直径，以被有源光纤吸收。 输入到锥形杆的光由多个高功率激光二极管产生，并被微透镜准直。 通过利用锥形杆将来自大功率二极管激光器的光耦合到泵浦光纤，可以实现高泵功率密度，产生增加的放大。
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公开(公告)号：US5108183A
公开(公告)日：1992-04-28
申请号：US565248
申请日：1990-08-09
CPC分类号： G01C19/721 , G01P3/36
摘要： An improved broadband light source for a Sagnac interferometer includes a waveguide, such as a fluorescent optical fiber, that is pumped by a pump source with a sufficient intensity to generate temporally incoherent light. The fluorescent optical fiber has first and second ends, one end being an input end of the fiber. The broadband light is provided at an output of the fluorescent optical fiber and is input to the interferometer. In order to prevent laser oscillations between the light source and the interferometer, one end of the fluorescent optical fiber is formed so as to prevent reflections. The light output from the fluorescent fiber to the interferometer comprises only that light that initially propagates toward the output of the optical fiber. In one embodiment of the light source, the pump light from the pump source is coupled into the fluorescent optical fiber in a direction so that it travels away from the output of the fluorescent optical fiber towards the first end. In an alternative embodiment, the fluorescent optical fiber is a doubly clad optical fiber having a first acceptance region and a second acceptance region at the first end. The pump light is introduced into an aperture window between the two acceptance regions so that the pump light can be introduced into the first end at an angle without requiring a reflective surface at the first end.
摘要翻译： 用于Sagnac干涉仪的改进的宽带光源包括诸如荧光光纤的波导，其由泵浦源以足够的强度泵浦以产生时间上不相干的光。 荧光光纤具有第一和第二端，一端是光纤的输入端。 宽带光被提供在荧光光纤的输出处，并被输入到干涉仪。 为了防止光源和干涉仪之间的激光振荡，形成荧光光纤的一端以防止反射。 从荧光纤维到干涉仪的光输出仅包括最初向光纤的输出传播的光。 在光源的一个实施例中，来自泵浦源的泵浦光沿着使得其从荧光光纤的输出朝着第一端行进的方向耦合到荧光光纤中。 在替代实施例中，荧光光纤是在第一端具有第一接收区和第二接收区的双包层光纤。 泵浦光被引入两个接受区域之间的孔眼窗口中，使得泵浦光可以一角度被引入第一端，而不需要第一端的反射表面。
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