共查询到19条相似文献,搜索用时 109 毫秒
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本文结合近场扫描结构和纳米线-微光纤耦合技术,提出了一种基于硫化镉纳米线/锥形微光纤探针结构的被动近场光学扫描成像系统.该系统采用被动式纳米探针,保留了纳米探针对样品表面反射光的强约束优势.其理论收集效率为4.65‰,相比于传统的金属镀膜近场探针收集效率提高了一个数量级,可有效地提高扫描探针对样品形貌信息的检测能力;而后通过硫化镉纳米线与微光纤之间高效的倏逝场耦合,将检测的光强信号传输到远场进行光电探测,最终实现对目标样品形貌的分析成像,其样品宽度测量误差在7.28%以内.该系统不需要外部激发光路,利用显微镜自身光源进行远场照明,被动扫描探针仅作为样品表面反射光的被动收集系统.本文基于半导体纳米线/锥形微光纤探针的被动式近场光学扫描成像方案,可有效地降低探针的制备难度和目标光场的检测难度,简化扫描成像的结构,为近场光学扫描显微系统之后的发展提供新的思路. 相似文献
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本文结合近场扫描结构和纳米线-微光纤耦合技术,提出了一种基于硫化镉纳米线/锥形微光纤探针结构的被动近场光学扫描成像系统.该系统采用被动式纳米探针,保留了纳米探针对样品表面反射光的强约束优势.其理论收集效率为4.65‰,相比于传统的金属镀膜近场探针收集效率提高了一个数量级,可有效地提高扫描探针对样品形貌信息的检测能力;而后通过硫化镉纳米线与微光纤之间高效的倏逝场耦合,将检测的光强信号传输到远场进行光电探测,最终实现对目标样品形貌的分析成像,其样品宽度测量误差在7.28%以内.该系统不需要外部激发光路,利用显微镜自身光源进行远场照明,被动扫描探针仅作为样品表面反射光的被动收集系统.本文基于半导体纳米线/锥形微光纤探针的被动式近场光学扫描成像方案,可有效地降低探针的制备难度和目标光场的检测难度,简化扫描成像的结构,为近场光学扫描显微系统之后的发展提供新的思路. 相似文献
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杭天渊刘凤王晓蕾叶松陈振涛 《光学与光电技术》2017,(4):26-32
在分析比较传统光纤探针研制工艺特点的基础上认为其不适用于蓝宝石光纤,因此提出了基于研磨抛光系统的光纤探针制备工艺。介绍了研磨系统的组成及运作方式,阐述了光纤探针制备过程中研磨抛光与固化的主要流程。最后使用光学仿真软件Zemax进行了光纤探针传输效率的仿真测试,仿真结果表明采用940nm波段光源及"面对面"探头安置方式时光纤探针传输效率最高。可应用于蓝宝石光纤探针传感器系统的搭建。 相似文献
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光纤倏逝波生物传感器光纤探头的耦合光束限定 总被引:3,自引:0,他引:3
根据光纤的模式匹配理论计算了给定条件下光纤探头的模式匹配半径,以此匹配半径为基础分析了激发光在锥型光纤探头中的光线传输轨迹.结果表明,在此条件下如不对光纤探头的耦合光束进行限定,将有一部分激发光在锥型光纤探头中因不满足全反射的传输条件而透射出光纤探头,从而使传感器系统得到虚假检测信息.针对此问题,在光纤倏逝波生物传感器的系统设计中给出了具体的解决方法. 相似文献
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光纤传感技术已广泛应用于航空航天、石油化工、电子电力、土木工程、生物医药等领域,其技术形式主要体现为分立式和分布式.分立式光纤传感技术利用光纤敏感器件作为传感器来感知被测参量的变化,光纤作为光信号的传输通道连接光纤传感器及后端的解调装置;分布式光纤传感系统基于光纤瑞利散射、拉曼散射或布里渊散射等光学效应,利用光纤本身作为传感器,可对沿途的光信号进行大范围、长距离传感.本文介绍了分立式与分布式光纤传感中主要关键技术的研究进展,并对未来的研究和发展方向进行了探讨. 相似文献
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A priority line of biomedical applications of optics is the development of noninvasive diagnostic methods based on the scanning of fluorescence radiation of biosensors embedded in biological tissue. Their main advantage is a high sensitivity and selectivity with respect to given parameters of tissues and their variations. In this study, we present a method for and results of modeling of excitation and propagation of fluorescence radiation in a multilayer randomly inhomogeneous highly scattering and absorbing medium imitating human skin. The model takes into account the spatially inhomogeneous distribution of skin fluorophores and their photophysical characteristics. Both the spatial distribution of fluorescence of skin tissues and the possibility of localization of a detected fluorescence signal are studied. The spatial distribution of fluorescence centers (fluorophores) in the medium is assumed to closely follow the spatial distribution of collagen fibers of the skin. The equalization of the refractive indices at the air-skin interface is shown to lead to a higher degree of localization of the fluorescence signal detected from a biosensor located in a near-surface skin layer. 相似文献
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A novel structure of fiber optic biosensor and its principle are introduced. The sample is detected in microchannels of several microns diameter in fiber optic biosensors. The relation between the optic fiber tapered angle and the fluorescence incident angle is calculated in signal receiving part. As the sensor is a zero-order system, calculating formula of the static sensitivity is derived. When ZnSe nano-crystalline cluster is used for marking the molecules, the static sensitivity for fiber optic biosensors is calculated. At the same time, the relation between the static sensitivity and the ratio of exciting wavelength to fluorescence wavelength is presented. 相似文献
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We investigated the incorporation efficiencies of different fluorescently labelled dNTPs with polymerases by complementary strand synthesis. For this reason single stranded DNA was immobilized on a coverslip and the increase of fluorescence due to the synthesis of the corresponding strand with tagged dNTPs was detected with a supercritical angle fluorescence biosensor in real-time. By comparison of the observed signal intensities it was possible to conclude that the system Cy5-dCTP-Klenow (exonuclease free) fragment gives the best incorporation yield of the investigated enzymes and dNTPs. 相似文献
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A new and compact fluorescence biosensor is constructed. The distinguished feature of this setup is the use of an ellipsoidal reflector as an optical collector of the fluorescence light. A traditional collecting lens with numerical aperture of 0.5 can only collect a few percent of the available signal, while the incorporation of the ellipsoidal reflector enables the apparatus to provide a signal increase of at least 66 times. A very good linear relationship between the concentration of fluorescent dye and the fluorescence intensity is achieved with correlation coefficient R=0.99979. The 3σ detection limit is 5 nM for microliter volume sample. Meanwhile, it is found that laser light scattering by dirts and scratches on the sample cell's windows and by turbidity in the sample solutions is the dominant limitation to increase the detection sensitivity. Approach to solve this problem is suggested. 相似文献
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对Goldview(GV)作为荧光标记物的DNA荧光毛细生物传感器进行了研究。以荧光毛细分析法(fluorescence capillary analysis, FCA)为基础, 在毛细管内壁通过Poly-l-lysine将20-mer-ssDNA探针固定, 制成DNA荧光毛细生物传感器(DNA fluorescence capillary biosensor, DNA-FCB),DNA-FCB与互补靶DNA杂交,通过GV染色后,检测杂交产物的荧光强度,实现对靶DNA的定性和定量分析。样品用量12 μL, 靶DNA的浓度在0.4~4 μmol·L-1(2.4~24 mg·L-1)范围内和荧光强度有良好的线性关系(y=65.911x+3.994 4,r=0.998 9);RSD<3.5%,检出限0.39 μmol·L-1(2.2 mg·L-1),能达到定量检测靶DNA的目的。用DNA-FCB测定靶DNA操作简便, 试样、试剂用量少,测定成本极低, 能大大减少环境污染。 相似文献
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A. N. Mikhnyuk 《Acoustical Physics》2009,55(3):411-416
Efficiency of the waveguide-matched algorithms of source localization is experimentally investigated. The algorithms determine the source coordinates from the differences in the times of signal propagation over different ray paths. 相似文献
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光纤生物传感器是现代生物传感技术中的一个非常重要的类别。当前,许多以荧光检测为手段的光纤生物传感器已经商品化了,但几乎都是依靠检测荧光指示剂的光强来获取生物信息,而直接利用生物样品的自体荧光光谱来获取生物信息的光纤传感系统却还未上市。利用自行研发的一套三维荧光光谱光纤传感系统对新鲜的人体乳腺组织切片进行了研究,实验结果表明乳腺癌变组织与正常组织的自体荧光光谱的峰位和峰强比值存在明显区别,这是因为癌变组织的生化成分发生了根本改变。尽管其间的规律还需进一步探索,但可以展望,自体荧光光谱技术与光纤生物传感技术的结合有潜力成为人体恶性肿瘤在线原位诊断的有利工具。 相似文献
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Photon-number distributions for parametric fluorescence from a nondegenerate optical parametric amplifier are measured with a novel self-homodyne technique. These distributions exhibit the thermal-state character predicted by theory. However, a difference between the fluorescence gain and the signal gain of the parametric amplifier is observed. We attribute this difference to a change in the signal-beam profile during the traveling-wave pulsed amplification process. 相似文献