共查询到19条相似文献,搜索用时 250 毫秒
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白光干涉在保偏光纤测量与对轴中的应用 总被引:4,自引:1,他引:3
本文根据白光干涉原理,研究了保偏光纤偏振色散和耦合系数的测量,保偏光纤连接时主轴夹角的调整,并获得了满意的实验结果,还对白光干涉技术在保偏光纤传感和器件方面的应用作了初步的讨论。 相似文献
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针对相位敏感光时域反射计型分布式光纤围栏入侵监测系统对外界干扰敏感、误报率高的问题进行了深入研究,比较了多种小波提取入侵信号突变特征方法,并提出一种基于多个小波分解结果进行综合判决来降低分布式光纤围栏误报率的方法.实验结果表明,多种小波分解可以分别提取不同层次的突变细节信息,为综合决策提供更完备的信息和条件,比单一判决能更有效降低系统误报率,室外长期测试可达到0-1次/24h,大大提高了分布式光纤围栏报警系统的稳定性和置信度水平. 相似文献
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分布反馈光纤激光器水听器设计与实验 总被引:2,自引:2,他引:0
为验证分布反馈光纤激光器水听器具有抗干扰强、动态范围大、灵敏度高等独特优点,进行了该水听器的系统设计,并给出分布反馈光纤激光器的输出特性曲线.采用非平衡M-Z光纤干涉仪进行分布反馈光纤激光器水听器的解调,结合工作点扫描和控制的测量方法,利用压电陶瓷相位调制器来进行相位补偿,使系统稳定工作在最灵敏处.采用制作的光纤干涉仪,搭建室内水听器模拟对比实验,通过扬声器产生1.34 KHz和7.24 KHz的高频周期激励信号,以及对水听器进行敲击激励,分析水听器的响应.进行了激光器水听器和压电水听器低频频响特性对比测试,实验得出光纤激光器水听器的光电探测输出信号的信噪比高,可以准确、可靠地反映原始声信号. 相似文献
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基于Bitaper-LPFG-Bitaper结构的全光纤Mach-Zehnder干涉仪的温度传感特性 总被引:1,自引:1,他引:0
提出并制作出一种基于锥体光纤-长周期光纤光栅-锥体光纤结构的全光纤Mach-Zehnder(M-Z)干涉仪传感器,并对其温度传感特性进行了研究.实验结果表明,固定光纤锥体和长周期光纤光栅的结构,仅改变两个光纤锥体之间的距离,对应不同的M-Z干涉谐振峰呈现出不同的温度传感特性:随着两个光纤锥体之间的距离增加,位于短波长处的谐振峰,传感器的温度灵敏度减小,而位于长波长处的谐振峰,传感器的温度灵敏度增加.当传感器长度为16.5 cm时,在1 680 nm附近的温度灵敏度达到0.102 06 nm/℃.实验结果对于锥体光纤-长周期光纤光栅组合型温度传感器的优化设计具有重要参考价值. 相似文献
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We demonstrated a fiber sensing system using the method of wavelength locking of two identical fibers Bragg gratings (FBG) to interrogate the wavelength shift by directly measuring the intensity of the reflection from the sensing Bragg grating. The light source of the fiber sensing system is an EDFA fiber ring laser pumped by a 980 nm laser diode and a narrow bandwidth fiber Bragg grating for the filter of the ring laser resonator. The wavelength shift is converted to the intensity deviation of the reflection from the sensing FBG under strain variation, and is able to achieve real-time sensing of the dynamic strain sensing in civil engineering. The characteristics and key factors to maintain stability of the dynamic strain sensing system are discussed. 相似文献
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光纤传感器系统中的功能光纤 总被引:2,自引:0,他引:2
本文结合光纤传感器的应用实例,对光纤传感器中光纤的选用进行了比较详细的讨论.光纤传感器是一种新型和具有一定特殊应用的传感器,如光纤陀螺、光纤流量计等,由于其自身的特点,具有其他传感器无法替代的优势.在这些传感器中,光纤的选用是致关重要的,特别是传感器用光纤的特性及对光纤传感器的影响;本文提出了光纤传感器设计过程中选用光纤的一些重要依据并论及了发展传感器用光纤对光纤传感器的重要意义. 相似文献
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A non-fused fiber coupler for side-pumping of double-clad fiber lasers 总被引:17,自引:0,他引:17
A non-fused fiber coupler is demonstrated for side-pumping of the double-clad fiber (DCF) lasers by adhesive techniques. The fiber coupler is fabricated by adhering an angularly polished single-clad fiber (SCF) to the inner cladding of the DCF. The pumping light is launched from the SCF by total inner reflection. Coupling coefficient as a function of coupling angle, bend distance, and backward scattering is investigated. The field distribution in DCF is also discussed. 相似文献
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W. Khunnam 《Optik》2010,121(14):1309-1312
We firstly present a concept of a self-calibration of the classical and quantum parameters’ measurement using a fiber optic system. The measurement of the change in phase of the optimum entangled states’ visibility is performed in terms of a walk-off length, i.e. birefringence. The applied physical parameters on the sensing fiber can be simultaneously measured and the self-calibration respecting the birefringence performed. The scheme of the entangled photons generation in fiber optic is reviewed and the walk-off on the polarization entangled states presented. The potential of self-calibration and simultaneous measurement using an interferometric sensing technique and fiber grating sensor are proposed and discussed. The walk-off on the entangled states in the thermal-controlled environment is presented and discussed. 相似文献
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Jianliang Yang Yunqi Liu Sweechuan Tjin Jianping Yao 《International Journal of Infrared and Millimeter Waves》2002,23(8):1241-1250
A photonics true-time-delay system for phased array antenna beam steering employing a novel tunable chirped fiber grating delay line and a multi-wavelength erbium-doped fiber ring laser source based on a sampled grating filter is proposed. The tunable chirped fiber grating, which act as a continuous time-delay element, is achieved by bending a uniform fiber Bragg grating bonded at a slant onto the lateral surface of a simply supported beam. This technique allows the dynamic control of the chirp rate and spectral width of the grating without center wavelength shift. By adjusting the chirp rate of the fiber grating via bend strain, this kind of tunable chirped fiber grating could achieve very low and adjustable delay times, therefore provides higher angle resolution for scanning microwave beam, even the wavelengths of laser source are fixed and un-tunable. The true-time-delay system using proposed tunable chirped fiber grating delay element and sampled grating based laser source is constructed and demonstrated experimentally. 相似文献
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Aïssa Harhira Francis Guay Maxime Daigle Raman Kashyap 《Optics Communications》2010,283(23):4633-4638
A new holographic technique is proposed for fabricating long-period fiber gratings (LPGs) using a CO2-laser and a phase mask. A CO2 laser operating at 10.6 μm is incident normally on the phase mask and the diffracted interfering beams imprint a thermally induced periodic modulation into the cladding of the fiber placed behind the mask. Preliminary results of this technique are presented and discussed. An unusual self-tapered fiber LPG (STFLPG) is also presented. 相似文献