基于强度调制的光纤SPR系统的研究

光纤表面等离子体共振(SPR)传感器是一种将光纤纤芯作为激发SPR效应基体的新型传感器.阐述了SPR效应及其强度调制原理.设计出一套基于共振光强度调制技术的光纤表面等离子体传感器系统,通过Labview直观的图形化界面对共振信号进行采集.利用此系统针对不同折射率的溶液进行测试,得到光强与折射率关系.     

基于光纤SPR传感器水中盐度的测定

论述了检测系统和基于拉锥技术的光纤表面等离子共振(SPR)传感器的详细设计.制定了基于SPR的光纤传感器检测水样品的盐度的比较方案,以满足一些实践需求,诸如精度,速度快,小尺寸和高灵敏度折射率单位(RIU).利用Matlab和C++仿真得到了每个参数对光纤拉锥SPR传感器系统设计性能的影响,这为设备参数的合理选择提供了理论依据.设计了一种新的检测系统,将光学、机械和电子技术相结合.根据拉锥技术、模场分析理论及初步实验结果表明,该装置基本上达到了设计要求,如小巧、便携、良好的线性度和高度单位折射率.基于这个新设备对具有不同的盐度的NACL-水混合物进行了SPR实验,实验结果表明,可以实现对单个样品的精确检测.其谐振波长分辨率可以达到0.15 nm,同时,该检测结果具有较高的线性度和良好的稳定性,折射率(RI)检测偏差小于0.002.     

基于色相算法的表面等离子体共振成像传感器

本文报道了一种基于色相算法的彩色表面等离子体共振(SPR)成像传感器,该传感器不仅能够对发生于SPR芯片表面的物理化学反应进行直观的图像观测,还能基于色相算法对这些表面反应进行定量分析。利用自制的波长/图像同步检测型SPR传感器,实验获得了不同共振波长对应的共振图像,然后借助色相算法求得每一幅共振图像对应的二维色相分布及其平均色相,建立了共振波长与图像平均色相的依赖关系,用于优化基于色相参数的SPR折射率灵敏度。实验选择起始共振波长为650nm,测得基于色相的折射率灵敏度为3 338/RIU,是基于共振波长的折射率灵敏度的1.49倍。利用彩色SPR成像技术能够直观地观测到金膜表面涂布的聚四氟乙烯薄膜的不均匀性,再通过计算图像局部区间的平均色相,可以定量获得不同薄膜厚度对应的折射率灵敏度。实验结果证明了基于色相算法的彩色SPR成像传感器明显优于常规SPR传感器。     

基于MSM结构的表面等离子体共振光纤折射率传感器

基于表面等离子体共振(SPR)效应,设计了一种基于多模-单模-多模(MSM)结构的光纤折射率传感器。采用光纤熔接的方式构成MSM结构,并且在单模光纤的表面涂覆二氧化钛/银(TiO2/Ag)复合膜构成传感单元。利用FDTD Solutions仿真分析了单模光纤长度与金属膜厚度对传感器性能的影响。结果表明:单模光纤长度越长,共振深度越深;TiO2/Ag复合膜中Ag膜厚度为50nm,TiO2膜厚度为20nm时,传感器性能最优,在1.33~1.41环境折射率范围内,传感器的灵敏度约为6 875nm/RIU。实验结果表明该光纤折射率传感器结构制作工艺简单、灵敏度高。     

光纤SPR传感器的信号检测及处理

光纤表面等离子体共振(SPR)传感器是目前应用在环境介质检测和生物大分子检测等方面的新型、高精度传感器。首先,以表面等离子体共振传感理论为基础,对系统检测结果进行数据处理,得出采用均值估计的线性模型。在不同时刻与相同环境介质下,检测某一溶液的十组光谱数据并进行均值估计,从而得到有效的共振波长。其次,利用小波分析方法进行信号处理,校正了噪声产生的漂移,对光谱信号压缩处理,以提高检测精度。再通过Matlab进行模拟仿真优化传感系统性能。并对不同折射率溶液如蒸馏水、酒精等进行检测,得到了良好的光谱响应曲线,证明了在检测范围内折射率和共振波长之间具有良好的线性关系。     

光纤SPR传感器参数对折射率测量灵敏度的影响

为了研究光纤表面等离子体共振(SPR)传感器参数对折射率测量灵敏度的影响，采用双频激光外差干涉相位测量光路结合光纤型SPR传感器进行了折射率测量，并对光纤SPR传感器不同纤芯直径对传感器灵敏度影响进行了分析。在光纤SPR传感器适应的折射率范围内，分别使用纤芯直径为300μm的光纤和400μm的光纤，测量不同质量分数下的甘油、蔗糖、氯化钠溶液的相位差，并计算对应折射率；分析了在传感器适用的折射率范围内，各溶液质量分数与折射率之间的关系，并对理论结果进行了实验验证。结果表明，纤芯直径越小，传感器灵敏度越高，灵敏度可达10^-5量级；密度越高，测量中的稳定性越高，最大相位差标准差为0.145°;分子量越大，精度越高，蔗糖的测量计算值与阿贝折射仪标定值之间的差值最大为0.52×10^-4。该研究为光纤SPR传感技术的进一步研究及应用提供了较好基础。     

光纤表面等离子体共振光化学传感器的原理及进展

以光纤传输技术和表面等离子体共振(SPR)技术有机结合的光纤表面等离子体共振传感器,是实现微量生物和化学活性物质定量测定的重要技术之一.介绍了光纤SPR传感器的结构,工作原理和调制方式.在最新进展中,介绍了现在应用广泛的分布式光纤SPR化学传感器,以及倾斜光栅和光子晶体这两种结构比较新颖的光纤SPR化学传感器.最后给出光纤SPR传感器的发展方向.     

波长检测型表面等离子体共振传感器的实验研究

介绍了表面等离子体共振(SPR)传感器的工作原理,设计了一套基于波长检测型Kretschmann结构的SPR传感测试系统。通过固定入射光角度,以波长为变量,测定了10种不同浓度的乙醇水溶液折射率与共振波长之间的对应关系。实验结果表明,共振波长随着样品折射率的增大而逐渐向长波长方向偏移,且两者之间呈现良好的线性关系。通过对共振光谱的分析,实现对未知溶液折射率或者浓度的测定。整个传感器系统具有结构紧凑、操作简单、实时检测和测量准确等优点。     

小波分析用于表面等离子体波光谱的噪声滤除

针对光纤表面等离子体波传感器,对小波阈值去噪的方法在测定表面等离子体波光谱中的应用进行了理论研究.首先将高斯白噪声加入理论SPR光谱,利用Daubechies9和Symlet7、11、14、1 5等五种小波分别对其进行去噪.将去噪后的共振峰强度和共振波长与理论值相比较,可知Symlet11小波用于SPR光谱的去噪性能较好.搭建光纤SPR传感器实验系统,利用Symlet11小波对在五个不同时刻测得的SPR反射光谱进行去噪,去噪后的共振波长和共振强度的标准偏差分别为0.4039 nm和0.2231%,通过对比证明小波阈值去噪方法能较好地修正由于噪声所产生的共振波长漂移,使得光纤SPR传感器满足实际运用的需要.     

基于表面等离子体共振的光纤传感技术研究

提出一种基于棱镜型表面等离子体共振光强度调制的光纤传感新方法。基于理论模型,分析了棱镜的介电常数和介质的折射率对SPR传感器共振角的影响,在此基础上讨论了光强调制型SPR测量方法的可行性。该方法与已有的光强度调制型棱镜SPR传感方法相比具有测量方便和可长距离应用等优点。     

Cost-effective test solutions for smart card and other integrated flash applications

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.     

Theoretical analysis of the relationship between the Brillouin gain coefficient and the strain in the optical-fiber sensors

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.     

Novel fiber-optical interferometer with miniaturized probe for in-hole measurements

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.     

An Improved parallel thinning algorithm with two subiterations

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.     

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.     

Diode-end-pumped Nd:YVO4/LBO lasers with 4.2W continuous-wave output at 457 nm

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.     

JOURNAL OF ELECTRONICS(CHINA)

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Call for Papers

正Introduction Jointly sponsored by the China Institute of Communications(CIC)and the IEEE Communications Society(IEEE ComSoc)since the year 2013,China Communications,currently,is aiming to gradually realise the transition from journal to magazine content and style.We are now looking for innovative technical papers pertinent to Information and Communications Technologies(ICTs)worldwide.Theoretical research papers     

Call for Papers

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     

Call for Papers—Feature Topic,Vol.12,No.7,2015

正Information Centric Networking Information-Centric Networking(ICN) is an emerging direction in Future Internet architecture research,gaining significant tractions among academia and industry.Aiming to replace the conventional host-to-host communication model by a data-centric model,ICN treats data content as the first