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公开(公告)号：US4452533A
公开(公告)日：1984-06-05
申请号：US286099
申请日：1981-07-22
摘要： A sensor for sensing conditions such as acoustic waves, temperature changes, acceleration current and magnetic fields. The sensor employs a diode laser having its cavity contained between end facets defined by partially reflective mirrors, supplemented by an external cavity formed between one of the end facets of the laser and a translatable external reflector. The reflector is position-responsive to a condition to be sensed. A change in the reflector's positions causes laser output light to be fed back through the mirror into the laser cavity with varying phase such that an increase or decrease in laser emission is created. A change of detector voltage or change in laser current provides an indication of environmental condition being sensed.
摘要翻译： 用于感测声波，温度变化，加速电流和磁场等条件的传感器。 该传感器采用二极管激光器，其腔体包含在由部分反射镜限定的端面之间，由在激光器的一个端面之间形成的外部空腔和可平移的外部反射器补充。 反射器对要感测的状态进行位置响应。 反射器位置的改变使得激光输出光通过反射镜反射回到具有变化相位的激光腔中，使得产生激光发射的增加或减小。 检测器电压的变化或激光电流的变化提供了感测环境条件的指示。
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公开(公告)号：US4600885A
公开(公告)日：1986-07-15
申请号：US610463
申请日：1984-05-15
IPC分类号： G01R33/032 , G01R33/02
CPC分类号： G01R33/0327
摘要： A fiber optic magnetometer for detecting DC magnetic fields includes a first optical fiber having a magnetostrictive jacket thereon which defines a sensing arm, and a second fiber defining a reference arm. An AC magnetic field of frequency .omega..sub.o and constant amplitude is imposed on the magnetostrictive jacket so as to cause a time varying optical path length change, having an .omega..sub.o component, in the sensing arm fiber. This induces a corresponding time varying phase shift, also having an .omega..sub.o component, in light transmitted through the sensing arm fiber which is detected by a phase detector. The phase detector produces a signal proportional to the phase shift, this signal being passed to a lock-in amplifier set to amplify at .omega..sub.o. The lock-in amplifier produces an output signal proportional to the amplitude of the .omega..sub.o component, wherein this amplitude is proportional to any DC magnetic fields to which the device is exposed.
摘要翻译： 用于检测直流磁场的光纤磁力计包括：第一光纤，其上具有限定感测臂的磁致伸缩护套，以及限定参考臂的第二光纤。 在磁致伸缩套管上施加频率ωo和恒定幅度的交流磁场，从而在感测臂光纤中产生具有ωo分量的时变光程长度变化。 这通过相位检测器检测到的通过感测臂光纤传输的光在同一时间变化的相移中也产生ωω分量。 相位检测器产生与相移成比例的信号，该信号被传递到锁定放大器，以在ωo上放大。 锁定放大器产生与ωo分量的幅度成比例的输出信号，其中该幅度与装置所暴露的任何DC磁场成比例。
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公开(公告)号：US5394378A
公开(公告)日：1995-02-28
申请号：US78887
申请日：1993-06-21
CPC分类号： G01D5/35383 , G01H9/004
摘要： A sensing portion for an interferometric planar hydrophone is disclosed which comprises: a support assembly; a plurality of hollow compliant mandrels mounted to the support assembly in a fixed planar relationship with respect to each other to form a planar configuration; a sensing optical fiber sequentially wound around each of the plurality of mandrels to form a single, serial, optical sensing arm or path between an input position on a first one of the plurality of mandrels and an output position on a last one of the plurality of mandrels; and an acoustically transparent material encapsulating the sensing portion to form a sealed compliant planar hydrophone. In an operational system, an interferometric planar hydrophone is disclosed which comprises: the sensing portion in which the sensing arm is operative to measure a predetermined measurand in a preselected environment and which sensing portion further includes a reference optical fiber environmentally isolated from the predetermined measurand; a light source for transmitting coherent light to both of the sensing and reference optical fibers; and circuitry responsive to light received from the sensing and reference optical fibers for developing an output signal indicative of phase shift differences between the sensing and reference optical fibers to determine the predetermined measurand.
摘要翻译： 公开了一种用于干涉式平面水听器的感测部分，其包括：支撑组件; 多个中空柔性心轴相对于彼此以固定的平面关系安装到支撑组件以形成平面构型; 感测光纤顺序地缠绕在所述多个心轴中的每一个上以在所述多个心轴中的第一个心轴上的输入位置与所述多个心轴中的最后一个上的输出位置之间形成单个，串联的光学感测臂或路径 心轴 以及封装感测部分以形成密封柔性平面水听器的声透明材料。 在操作系统中，公开了一种干涉式平面水听器，其包括：感测部分，其中感测臂可操作以在预选环境中测量预定的被测量，并且感测部分还包括与预定被测量环境隔离的参考光纤; 用于将相干光传输到感测和参考光纤两者的光源; 以及响应于从感测和参考光纤接收的光的电路，用于开发指示感测和参考光纤之间的相移差的输出信号，以确定预定的被测量。
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4.依法登记的发明
公开(公告)号：USH864H
公开(公告)日：1991-01-01
申请号：US464497
申请日：1990-01-12
申请人： Frank Bucholtz , Kee P. Koo , Anthony Dandridge , Alan B. Tveten
发明人： Frank Bucholtz , Kee P. Koo , Anthony Dandridge , Alan B. Tveten
IPC分类号： G01R33/032
CPC分类号： G01R33/0327
摘要： Improved passive and laser-conditioned magnetic field sensor of compact and integrated construction for enabling the detection of a magnetic field as well as an improved method of manufacture for assembling and selectively pretensioning a subassembly in order to provide an enhanced formation of the subassembly prior to use. The sensor is generally made up of a magnetic field sensing device, first and second fiber-optic elements, first and second couplers, a laser source and a combined detector and analysis means. The first and second couplers interconnect the first and second fiber-optic elements. The magnetic field sensing device is advantageously connected to one of the fiber-optic elements and is generally made up of a magneto-strictive material (MSM) of ribbon-like shape, a nonmagnetic substrate and a sensing element of optic fiber construction. This element is of predetermined and selective multistrand design between its ends and of generally serpentine shape. The sensing device is advantageously formed such that the MSM and the sensing element are uniformly and selectively pretensioned. As the result of this pretensioning, the MSM elongates when a magnetic field is detected thereby decreasing the elongation of the sensing element. Despite this decrease, the sensing element remains tensioned because of sufficient pretensioning and the phase shift in the laser as it is conducted through the optic fiber is detectable by the combined means.
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公开(公告)号：US4653915A
公开(公告)日：1987-03-31
申请号：US722580
申请日：1985-04-12
CPC分类号： G01B9/02027
摘要： A passive device for reducing polarization fading in interferometers with significantly degrading the signal-to-noise ratio. In one embodiment, light from an interferometer output is passed through a lens to a polarization mask. The polarization mask comprises at least three distinct polarizers which pass distinct states of polarization. After passing through the polarizers each independently polarized signal is detected, demodulated and passed to a means for signal extraction.
摘要翻译： 用于减少干涉仪中的偏振衰落的无源器件，而不会明显降低信噪比。 在一个实施例中，来自干涉仪输出的光通过透镜到达偏振掩模。 偏振掩模包括通过不同极化状态的至少三个不同的偏振器。 在通过偏振器之后，每个独立的偏振信号被检测，解调并传递到用于信号提取的装置。
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6.发明授权公开(公告)号：US06611633B1
公开(公告)日：2003-08-26
申请号：US09534047
申请日：2000-03-24
IPC分类号： G02B600
摘要： This invention pertains to a sensor comprising of glass optical fiber, a cellular pressure release material surrounding the fiber, and means for determining responsivity of the sensor, the sensor having responsivity of at least about −160 dB re rad/m-&mgr;/Pa, which corresponds to sensitivity of about 50 times better than prior art. The sensor can be made part of an optical interferometer which is characterized by splitting of an entering light beam and measurement of an optical phase shift caused by light traversing different paths. The sensor can form a part of a fiber Bragg grating geometry characterized by a fiber Bragg grating in the glass fiber covered by the cellular pressure release material wherein shift of the Bragg wavelength induced by strain on to the cellular pressure release material is measured.
摘要翻译： 本发明涉及包括玻璃光纤，围绕光纤的蜂窝压力释放材料和用于确定传感器的响应度的装置的传感器，该传感器具有至少约-160dB雷达/ m-mu / Pa的响应度， 这对应于比现有技术好约50倍的灵敏度。 传感器可以制成光干涉仪的一部分，其特征在于分离进入的光束和由穿过不同路径的光引起的光学相移的测量。 传感器可以形成光纤布拉格光栅几何的一部分，其特征在于由细胞压力释放材料覆盖的玻璃纤维中的光纤布拉格光栅，其中测量由应变引起的布拉格波长向细胞压力释放材料的偏移。
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公开(公告)号：US5668779A
公开(公告)日：1997-09-16
申请号：US625081
申请日：1996-03-29
摘要： A hydrophone group for shallow towed applications in less than 50 feet of ter. The hydrophone group has a series of hydrophones connected by relatively insensitive fiber optic interconnects. The individual hydrophones are sufficiently sensitive such that the interconnecting optical fiber does not introduce excessive noise. Each hydrophone is basically a sensing fiber wrapped around an air-backed mandrel. Each air-backed mandrel is formed of an extended solid frame substantially non-compliant along a longitudinal axis. The extended solid frame is provided with a channel around the periphery thereof. The channel extends substantially the entire length of the extended solid frame. A flexible outer covering surrounds the extended solid frame. The flexible outer covering is highly compliant in a radial direction extending from the longitudinal axis. The air-backed mandrel has a high frequency mechanical resonance. Each hydrophone is connected in a chain by a plurality of interconnects having a substantially lower sensitivity than each hydrophone.
摘要翻译： 在50英尺以下的水中，用于浅拖曳应用的水听器组。 水听器组具有通过相对不灵敏的光纤互连连接的一系列水听器。 各个水听器是足够敏感的，使得互连光纤不会引起过大的噪声。 每个水听器基本上都是围绕空气轴承的感应纤维。 每个空气支撑的心轴由沿着纵向轴线基本不顺从的延伸的实心框架形成。 延伸的实心框架围绕其周边设置有通道。 通道基本延伸延伸的固体框架的整个长度。 柔性外覆盖物围绕扩展的实心框架。 柔性外覆盖件在从纵向轴线延伸的径向方向上是高度柔顺的。 空气轴承的心轴具有高频机械共振。 每个水听器通过具有比每个水听器明显更低的灵敏度的多个互连件连接在链中。
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