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三分量全光纤加速度地震检波器的设计 总被引:10,自引:5,他引:10
本文介绍了顺变柱体型三分量全光纤加速度地震检波器。该检波器由1个质量量块,6个顺变柱体,3套迈克尔逊干涉仪光路组成。其单一轴向的加速度可达10^3rad/g(其中,g为重力加速度),可同时检测3个轴向的加速度ax、ay、az,矢量合成得空间加速度a,从而实现加速度的实时、高精度检测。 相似文献
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双膜片结构光纤光栅地震检波器低频特性的研究 总被引:2,自引:2,他引:2
提出了一种双膜片式的光纤光栅(FBG)地震检波器,此结构有效限制了检波器横向响应。对该检波器的纵向加速度灵敏度和幅频特性进行了理论分析,并指出了影响这种检波器纵向加速度灵敏度的因素。实验结果表明,该种检波器在5~200Hz频率范围内频响平坦,纵向加速度灵敏度为24.3pm/g,谐振峰在900Hz附近,与理论计算较好的吻合。 相似文献
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基于双金属膜片结构的海底地震勘探光纤加速度传感器研究 总被引:2,自引:2,他引:0
针对全光海底地震检波器技术的特殊应用需求,设计了一种基于双金属矩形膜片的缠绕式光纤加速度传感器。利用弹性力学理论对光纤加速度传感器的加速度灵敏度和一阶共振频率的特性进行了分析,制作了光纤加速度传感器样品并对其性能进行了测试。结果表明,本文加速度传感器的灵敏度为45dB re∶0dB=1rad/g,一阶共振频率在820Hz左右,与理论分析值很好吻合。在10~400Hz工作带宽中,交叉去敏度约为30dB。测试系统中,使用的相位生成载波(PGC)解调算法的最小相位检测精度为10-5 rad/Hz1/2,因此理论能探测的最小加速度信号为56ng/Hz1/2。由于采用全金属结构,本文类型光纤加速度传感器能够更好地满足海底永久布放检波器的特殊要求。 相似文献
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三分量全保偏光纤加速度传感器的研究 总被引:5,自引:2,他引:5
报道了三分量全保偏光纤加速度传感器的实验研究结果。传感器由6个弹性柱体共同支撑1个质量块构成三分量结构,由3个迈克尔逊全保偏光纤干涉仪共用一个光源组成。光学部分采用全保偏光纤干涉仪结构,消除了干涉光束偏振态随机变化引起的信号衰落,采用光频调制相位载波解调信号处理技术,消除了相位随机漂移引起的信号衰落,从而实现了对加速度信号的稳定检测。传感器的工作频带为5~500 Hz,加速度灵敏度达到660 rad/g,系统最小可测相位差为10-5rad,最小可测加速度达1.5×10-7m/s2,工作频带内加速度灵敏度变化小于2 dB。三轴加速度灵敏度和频率响应曲线与理论分析的结果基本一致。 相似文献
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一种可用于油藏监测的3分量光纤加速度传感器 总被引:3,自引:1,他引:2
研制了一种可用于油藏监测的3分量光纤加速度传感器。该传感器通过3个单方向传感单元分别获得3个正交方向上的被测加速度分量,每个传感单元是一质量-弹簧系统,通过波纹管与顺变材料构成复合弹性体,并采用光纤干涉结构将被测加速度通过解调光纤中的相位变化反映出来。实验数据表明,该加速度传感器具有良好的线性度、一致性和稳定性。系统的工作频带范围为10Hz至800Hz,其轴向灵敏度为38dB re rad/g,交叉法去敏度达到32dB re rad/g,最小可检测加速度为39.3μg/Hz^1/2。 相似文献
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研制了基于时分外差法检测的非对称薄壁壳型光纤一维地震波检波器, 该检波器易于扩展为三轴分立式地震波检波器, 具有检测动态范围大, 易于构成大规模时分复用传感网络的优点。建立了非对称地震波检波器的理论模型, 分析了各结构参数对其灵敏度的影响; 搭建了基于光学同步参考信号的时分外差法测试系统, 进行了外差系统的稳定性测试, 测量了地震波检波器的频响曲线, 结果表明外差系统测量信号波动小于0.1dB; 工作频段20~800Hz内加速度平均灵敏度为28.5dB re rad/g, 与理论仿真结果基本吻合。 相似文献
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Michael Reilly 《半导体技术》2004,29(12)
DUV lithography, using the 248 nm wavelength, is a viable manufacturing option for devices with features at 130 nm and less. Given the low kl value of the lithography, integrated process development is a necessary method for achieving acceptable process latitude. The application of assist features for rule based OPC requires the simultaneous optimization of the mask, illumination optics and the resist.Described in this paper are the details involved in optimizing each of these aspects for line and space imaging.A reference pitch is first chosen to determine how the optics will be set. The ideal sigma setting is determined by a simple geometrically derived expression. The inner and outer machine settings are determined, in turn,with the simulation of a figure of merit. The maximum value of the response surface of this FOM occurs at the optimal sigma settings. Experimental confirmation of this is shown in the paper.Assist features are used to modify the aerial image of the more isolated images on the mask. The effect that the diffraction of the scattering bars (SBs) has on the image intensity distribution is explained. Rules for determining the size and placement of SBs are also given.Resist is optimized for use with off-axis illumination and assist features. A general explanation of the material' s effect is discussed along with the affect on the through-pitch bias. The paper culminates with the showing of the lithographic results from the fully optimized system. 相似文献
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Thomas M.Trexler 《半导体技术》2004,29(5)
From its emergence in the late 1980s as a lower cost alternative to early EEPROM technologies, flash memory has evolved to higher densities and speedsand rapidly growing acceptance in mobile applications.In the process, flash memory devices have placed increased test requirements on manufacturers. Today, as flash device test grows in importance in China, manufacturers face growing pressure for reduced cost-oftest, increased throughput and greater return on investment for test equipment. At the same time, the move to integrated flash packages for contactless smart card applications adds a significant further challenge to manufacturers seeking rapid, low-cost test. 相似文献
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The relation between the power of the Brillouin signal and the strain is one of the bases of the distributed fiber sensors of temperature and strain. The coefficient of the Bfillouin gain can be changed by the temperature and the strain that will affect the power of the Brillouin scattering. The relation between the change of the Brillouin gain coefficient and the strain is thought to be linear by many researchers. However, it is not always linear based on the theoretical analysis and numerical simulation. Therefore, errors will be caused if the relation between the change of the Brillouin gain coefficient and the strain is regarded as to be linear approximately for measuring the temperature and the strain. For this reason, the influence of the parameters on the Brillouin gain coefficient is proposed through theoretical analysis and numerical simulation. 相似文献
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The parallel thinning algorithm with two subiterations is improved in this paper. By analyzing the notions of connected components and passes, a conclusion is drawn that the number of passes and the number of eight-connected components are equal. Then the expression of the number of eight-connected components is obtained which replaces the old one in the algorithm. And a reserving condition is proposed by experiments, which alleviates the excess deletion where a diagonal line and a beeline intersect. The experimental results demonstrate that the thinned curve is almost located in the middle of the original curve connectivelv with single pixel width and the processing speed is high. 相似文献
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Today, micro-system technology and the development of new MEMS (Micro-Electro-Mechanical Systems) are emerging rapidly. In order for this development to become a success in the long run, measurement systems have to ensure product quality. Most often, MEMS have to be tested by means of functionality or destructive tests. One reason for this is that there are no suitable systems or sensing probes available which can be used for the measurement of quasi inaccessible features like small holes or cavities. We present a measurement system that could be used for these kinds of measurements. The system combines a fiber optical, miniaturized sensing probe with low-coherence interferometry, so that absolute distance measurements with nanometer accuracy are possible. 相似文献
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Qi-jiang Ran Pei-de Han Yu-jun Quan Li-peng Gao Fan-ping Zeng Chun-hua Zhao 《光电子快报》2008,4(4):239-242
This paper presents a new method to increase the waveguide coupling efficiency in hybrid silicon lasers. We find that the propagation constant of the InGaAsP emitting layer can be equal to that of the Si resonant layer through improving the design size of the InP waveguide. The coupling power achieves 42% of the total power in the hybrid lasers when the thickness of the bonding layer is 100 nm. Our result is very close to 50% of the total power reported by Intel when the thickness of the thin bonding layer is less than 5 nm. Therefore, our invariable coupling power technique is simpler than Intel's. 相似文献
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It is well known that adding more antennas at the transmitter or at the receiver may offer larger channel capacity in the multiple-input multiple-output(MIMO) communication systems. In this letter, a simple proof is presented for the fact that the channel capacity increases with an increase in the number of receiving antennas. The proof is based on the famous capacity formula of Foschini and Gans with matrix theory. 相似文献
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Teleportation of an arbitrary unknown N-qubit entangled state under the controlling of M controllers
A new quantum protocol to teleport an arbitrary unknown N-qubit entangled state from a sender to a fixed receiver under M controllers(M < N) is proposed. The quantum resources required are M non-maximally entangled Greenberger-Home-Zeilinger (GHZ) state and N-M non-maximally entangled Einstein-Podolsky-Rosen (EPR) pairs. The sender performs N generalized Bell-state measurements on the 2N particles. Controllers take M single-particle measurement along x-axis, and the receiver needs to introduce one auxiliary two-level particle to extract quantum information probabilistically with the fidelity unit if controllers cooperate with it. 相似文献
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A continuous-wave (CW) 457 nm blue laser operating at the power of 4.2 W is demonstrated by using a fiber coupled laser diode module pumped Nd: YVO4 and using LBO as the intra-cavity SHG crystal With the optimization of laser cavity and crystal parameters, the laser operates at a very high efficiency. When the pumping power is about 31 W, the output at 457nm reaches 4.2 W, and the optical to optical conversion efficiency is about 13.5% accordingly. The stability of the out putpower is better than 1.2% for 8 h continuously working. 相似文献
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《中国通信》2014,(7)
正Wireless Body-area Networks The last decade has witnessed the convergence of three giant worlds:electronics,computer science and telecommunications.The next decade should follow this convergence in most of our activities with the generalization of sensor networks.In particular with the progress in medicine,people live longer and the aging of population will push the development of wireless personal networks 相似文献