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适用于硅微谐振器件测量的光纤位移传感器研究 总被引:1,自引:1,他引:0
对一种适用于硅微机械谐振器件测量的光纤位移传感器进行了研究,该光纤位移传感器探头采用了单根光纤探测形式和光纤“X”耦合器结构,在微弱光电传感信号处理上采用了“锁相放大器”提取方案,可以实现对静态位移和振动位移两种场合进行测量.对该传感器的实测结果表明:该传感器测量范围为0~100 μm,测量灵敏度3.95 mV/μm,精度等级优于1%,重复性优于0.5%.为作为应用实例,运用该传感系统对一种微悬臂梁硅微谐振器件进行了测量,成功提取了硅微谐振器件的微弱谐振信号,证实了该传感器可以实现对硅微谐振器件的非接触和无损测量,并具有非接触、易调试、高灵敏度等优点. 相似文献
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分时复用光纤光栅振动传感器阵列 总被引:1,自引:0,他引:1
结合基于3×3耦合器的光纤Mach-Zehnder干涉仪和可调谐光纤Fabry-Perot滤波器(Fiber-Fabry-Perot,FFP),提出了一种分时复用光纤光栅振动传感器的技术.用FFP对串联在一根光纤上的光纤光栅的波长进行轮流扫描,让光栅的反射光按波长顺序依次通过FFP.而对于每一光纤光栅上外加的振动信号,用光纤Mach-Zehnder干涉仪进行测量.实际测量结果显示,FFP结合Mach-Zehnder能够对每一只光栅上的振动信号进行分时测量. 相似文献
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针对光纤振动传感器受温度影响和灵敏度低的问题,设计了具有温度补偿功能的光纤振动测量系统.为减小温度对振动测量的影响,系统利用光纤布喇格光栅测量环境温度,对振动加速度值进行补偿;采用可调谐法布里-珀罗滤波器进行波长解调,并将其作为光纤反射镜,以提高传感器的灵敏度.分析并测试了振动和温度同时测量时的相互影响,结果表明,振动对光纤布喇格光栅中心波长的影响很小,通过数据处理的方法,可消除法布里-珀罗滤波器扫描对振动测量的影响;实验测得,温度变化25℃时,振动加速度最大相对测量误差为1.65%,振动测量的灵敏度为107.70mV/g. 相似文献
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亚波长直径微纳光纤强倏逝场传输的光学特性,使其对周围介质折射率的变化具有极高的灵敏度.本文提出一种基于微纳尺度光纤布拉格光栅(MNFBG)的折射率传感器,结合微纳光纤倏逝场传输和光纤布拉格光栅(FBG)强波长选择的特性来实现高精度折射率传感,对其制备可行性进行了讨论.论文中对MNFBG折射率传感机理进行了深入的理论分析,并使用OptiGrating软件进行了数值模拟,模拟数据显示MNFBG折射率测量的灵敏度随着光纤半径的减小而增加,其中光纤半径为400 nm的MNFBG灵敏度可达到993 nm/RIU,相比于包层蚀刻的FBG灵敏度增加了170倍,说明MNFBG对发展微型化、高灵敏度折射率传感器具有良好的应用前景.
关键词:
微纳光纤
光纤布拉格光栅
折射率传感 相似文献
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设计并验证了一种基于分布布拉格反射(DBR)光纤激光器的高灵敏度微振动传感器。该传感器结构采用常见的质量块弹簧系统,质量块由于重力作用对DBR激光器的谐振腔产生侧向压力。当测试平台发生振动时,谐振腔所受到的侧向压力发生变化,导致激光器输出的两正交偏振模式产生的拍频信号改变。通过高速光电探测器和多通道数据采集平台对拍频信号进行采集,使用LabVIEW编程对采集信号进行处理,实现了对振动加速度信号的实时监测。理论分析与实验结果表明,该传感器具有极高的加速度灵敏度,对于单位重力加速度g其灵敏度达吉赫兹量级,能检测到微弱的振动信号。相较于传统光纤振动传感器而言,该传感器将光谱分析转化为频谱分析,使信号的采集与解调更加简单,且获得了更高的灵敏度。进一步分析表明,此结构在微重力环境下进行测量也是可行的,因此,在航空飞行器关键部件的微振动测量中有较大的应用潜力。 相似文献
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光纤振动传感器探头的设计 总被引:2,自引:0,他引:2
提出和论述了一种光纤振动传感器的原理和探头设计方法。使用悬臂梁来遮挡反射回光纤的光 ,用光强度调制来实现振动信号的测量。这种传感探头只需一根光纤引出 ,紧凑小巧 ,易于安装调试。结果表明 ,这种光纤振动传感器传感头是可靠而耐用的 ,长时间工作稳定 ,抗外界干扰强 ,易制作 ,易安装。 相似文献
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Yanyan Dong Yanfang Lu Changyu Shen Jinlei Chu Xin Zou Chuan Zhong Xinyong Dong 《Optik》2013,124(24):6737-6739
A novel bending sensor based on a long period fiber grating (LPG) is presented. A LPG was glued into a V-shaped groove, which lies on the lower surface of a meniscus shaped beam. It is found that the transmission optical power of the LPG changed linearly with the variation of the bending of the beam. The bending applied on the beam can be measured by detecting the intensity variation of the LPG's resonant dip wavelength. Under a relative large bending measured range from 0 to 7.5 m?1, the sensitivity of 3.003 dB m?1 and curvature resolution of 0.001 m?1 have been achieved for the proposed bending sensor. 相似文献
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Shinn-Fwu Wang 《Optics and Lasers in Engineering》2009,47(10):1039-1043
In this paper, an optical fiber sensor based on multiple total internal reflections (MTIRs) in heterodyne interferometry is proposed. With the optical fiber sensor the phase shift difference due to the multiple total internal reflections effect between the p- and s-polarizations is measured by using heterodyne interferometry. Substituting the phase shift difference into Fresnel's equations, the refractive index for the tested medium can be calculated. The resolution of the sensor can reach 1.6×10?6 refractive index unit (RIU). The optical fiber sensor could be valuable for chemical, biological and biochemical sensing. It has some merits, such as, high resolution and stability, high sensitivity, high resolution and real-time measurement. 相似文献
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A new scheme of optical film sensor is presented. The sensor is based on p-polarized reflectance, consisting of a sensing coated substrate, is easily optimized for maximum sensitivity in different applications. The resolutions of refractive index nf, extinction coefficient kf and thickness hf of the sensitive films are predicted to be 10−7, 10−5 and 10−3 nm, respectively. Experimentally, we selected the sol–gel derived SnO2 films as gas-sensitive films and conducted preliminary gas-sensing test. The results indicate that novel optical film sensor scheme has higher sensitivity, and the detection sensitivity is available to 10−1 ppm on the condition of optimum optical parameters and incident angle. 相似文献
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Highly-sensitive silicon-on-insulator sensor based on two cascaded micro-ring resonators with vernier effect 总被引:1,自引:0,他引:1
A highly-sensitive integrated optical biosensor based on two cascaded micro-rings resonator (MRR) is investigated theoretically and experimentally. The free spectral ranges (FSRs) of two cascaded micro-rings are designed to be slightly different in order to generate Vernier effect. A preliminary investigation of our sensor with a Q factor of 2 × 104 using different ethanol concentrations shows that the Vernier effect can improve the sensitivity to 1300 nm per refractive index unit (RIU), compared to 62 nm/RIU for a single ring sensor. The sensor also has a large measurement range of refractive index change up to 1.15 × 10− 2 RIU. It can be useful for low-cost and highly-sensitive optical biosensor system. 相似文献
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A novel waveguide ring resonator optical sensor with two resonant wavelength channels is proposed for a refractive index measurement
of a test sample placed on the sensor substrate and its performance characteristics are investigated analytically and numerically.
The waveguide device consists of a ring resonator, a split-ring-shaped loop waveguide, and a vertical input/output grating
coupler, in which the loop waveguide acts as an additional resonator and provides another output wavelength channel of the
sensor. The differential detection between the two wavelength channels enables the highly sensitive detection with temperature
compensation. A numerical simulation based on a finite difference time domain (FDTD) method shows that a precise index change
detection with a resolution of 10−6 can be achieved using of the proposed device. 相似文献
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Optical sensing by silicon slot-based directional couplers 总被引:1,自引:0,他引:1
A theoretical investigation of an optical liquid sensor, based on asymmetric directional coupler employing slot optical waveguides, is carried out. The sensing principle is based on the shift in the waveguide transmitted spectrum induced by analyte refractive index change. Silicon-on-insulator technology has been assumed in sensor design, and sensor modelling is carried out by using the coupled modes theory and the finite element method. The influence of geometrical parameters on the sensor characteristics has been investigated. A minimum detectable refractive index change of the order of 10?6 can be theoretically predicted. 相似文献
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NAVNEET K SHARMA 《Pramana》2012,78(3):417-427
The capability of various metals used in optical fibre-based surface plasmon resonance (SPR) sensing is studied theoretically.
Four metals, gold (Au), silver (Ag), copper (Cu) and aluminium (Al) are considered for the present study. The performance
of the optical fibre-based SPR sensor with four different metals is obtained numerically and compared in detail. The performance
of optical fibre-based SPR sensor has been analysed in terms of sensitivity, signal-to-noise (SNR) ratio and quality parameter.
It is found that the performance of optical fibre-based SPR sensor with Au metal is better than that of the other three metals.
The sensitivity of the optical fibre-based SPR sensor with 50 nm thick and 10 mm long Au metal film of exposed sensing region
is 2.373 μm/RIU with good linearity, SNR is 0.724 and quality parameter is 48.281 RIU − 1. The thickness of the metal film and the length of the exposed sensing region of the optical fibre-based SPR sensor for each
metal are also optimized. 相似文献
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A novel active optical approach for acceleration measurement based on a Y-shaped cavity dual-frequency laser is presented and demonstrated. Applied acceleration causes a change in the refractivity of sensing gas in one of the two cavities, resulting in a beat frequency variation between two orthogonal polarized lights. As a result, this approach produces a modulation of beat frequency strictly proportional to the input acceleration. Preliminary experiments with a 632.8 nm Y-shaped cavity He–Ne dual-frequency laser confirm the validity of the laser sensor. The experimental results show that the laser sensor in this approach characterizes a nearly linear response to the input acceleration, which is a projection of gravitational acceleration. The experimental values of the scale factors are mostly in good agreement with theoretical ones. By optimizing the optical and geometrical parameters of the laser sensor, an acceleration measurement resolution of 10?5–10?6 gravitational acceleration (within ±5 g measurement range) could be expected. Furthermore, we investigate the principle about the sign of the scale factor in detail, and propose a simple but efficient method to distinguish the direction of the acceleration acted on the laser sensor. 相似文献
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A new selective and sensitive optical sensor based on the incorporation of new synthesized N′-(2-hydroxy-5-iodobenzylidene) isonicotinohydrazide (HIBIN) as an effective reagent into the nanoporous of a transparent glass like material through the sol–gel process was developed which was suitable for the determination of copper (II) ions in aqueous solutions. The thin film sensors were constructed by spin-coating of prepared sol onto glass plate and their surface morphology were studied by field emission scanning electron microscopy (FE-SEM) and atomic force microscope (AFM) technique. Influence of sonication time on immobilization of HIBIN into silica matrix was investigated through calculation of leaching percentage. The Results shown that sonication time of 35 min is suitable to give more stable thin films without fluctuation in sensitivity and response time of presented sensor for a long period of time. The proposed optical sensor can be used for determination of copper (II) ions in the range of 9.1 × 10−8–1.12 × 10−5 mol L−1with a detection limit of 1.8 × 10−8 mol L−1. It also showed relative standard deviation 3.4 and 0.72% for reproducibility and repeatability respectively, along with a fast response time about of 2 min. The constructed optode is stable in wet conditions and could be stored for at least 6 weeks without observing any change in its sensitivity. The developed sensor was successfully applied to the determination of copper (II) in fruit juice and water samples which results were confirmed by atomic absorption spectrometry method. 相似文献
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Y. Sarov T. Ivanov K. Ivanova V. Sarova I. Capek I.W. Rangelow 《Applied Physics A: Materials Science & Processing》2006,84(1-2):191-196
This work presents the principles of a novel micro-optical system for micro- and nano-fluidic analysis. It is based on diffraction, occurring in total internal reflection conditions. The developed detector is integrated in an autonomous micro-fluidic device, produced by a unique combination of different techniques for micro- and nano-structuring and micro-machining. The micro-fluidic sensor is examined both experimentally and theoretically with respect to the parameters of the light and the diffraction grating. The most beneficial configurations with respect to maximum sensitivity towards the fluidic optical constants are discussed. Optical experiments show sensitivity of 5×10-4 to the fluidic refractive index and of 3.5×106 m-1 to the absorption coefficient. Envisioned applications of the integrated micro-sensor are concentration and composition analysis, environmental protection control, medical, biological and chemical diagnostics, and so on. PACS 07.07.Df; 81.16.-c; 78.20.Ci; 81.70.Jb 相似文献