共查询到19条相似文献,搜索用时 859 毫秒
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近场光镊是近场光学领域中的新型技术,因其可对纳米尺度微粒直接进行捕获和操纵而受到广泛关注.简述了该技术的原理,详细介绍了近场光镊技术的研究进展及其在众多学科领域中的潜在应用. 相似文献
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介绍了近场光学中的倏逝场的产生、数字表示以及它的一些特性,还述及了它的控制和近场光学显微镜的改进方向. 相似文献
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郭志和刘泽田陈启敏黄豪杰任洪亮 《激光与光电子学进展》2017,(9):33-44
光镊是一门利用光的动量与物质相互作用产生光势阱效应以实现粒子捕获的重要技术,该技术被广泛应用于纳米或微米级微粒的捕获及操控领域。当今技术和需求的发展对光镊系统的光束变换提出了更高的要求,因此需要对捕获光源的光束进行整形,获得光镊所需的光场分布。以激光光束整形的器件为主线,分别介绍在光镊系统中使用棱镜、衍射光学元件、液晶空间光调制器、数字微镜器件、光纤等光学元件进行捕获光源光束整形的情况。列出了这些器件组成的典型整形光路,以及近年来这些器件在光束整形方面的研究进展。同时还介绍了在捕获光源的整形设计中,上述方法的各自特点及相应的捕获能力。 相似文献
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在可见光波段,传统光学显微镜的成像分辨率被限制到200nm。为了突破衍射极限,采用了将微球与传统光学显微镜相结合的方法来获得远场超分辨率成像。首先通过理论分析平行光通过微纳结构物体后物光波在空气中的传输,进而分析微球将倏逝波转换成传输波实现远场超分辨的成像机理;其次通过仿真研究了微球的光纳米喷射特性,可知微球光纳米喷射的半径尺寸小于入射光波长的一半;最后搭建了基于微球与传统光学显微镜相结合的超分辨率成像实验系统。结果表明,将蓝光光盘作为被测物体,通过该成像系统可获得100nm的远场超分辨率成像; 该成像系统可以对微纳元件结构进行检测。这一结果对光刻技术、生物医学等领域是有帮助的。 相似文献
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基于光镊机理与倒置显微成像方法成功实现了铌酸锂微晶颗粒的光学捕获控制和光致取向的直接观测.由于铌酸锂微晶具有光学各向异性性质,所以在线偏振飞秒激光的操控下,所捕获的铌酸锂微晶颗粒能够依据激光偏振方向成功实现光控制取向.分析了铌酸锂微晶颗粒的激光控制取向机理,说明了铌酸锂微晶颗粒的取向可以利用激光的线性偏振方向进行光致取向旋转,有望应用于微纳光子学、MEMS、光控微型马达和微操作等科学研究领域. 相似文献
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多功能光学微操纵平台及应用 总被引:2,自引:1,他引:1
多功能光学微操纵平台是一种新型的微操控、微加工和微测量系统,它集成了光镊、飞秒激光光刀、显微光谱仪等多种功能.它对微小"工件",如生物细胞、细胞器及其它微小粒子的夹持、操作和微加工都是通过光来实现的,没有任何机械接触.它具有研究个体活体,实时动态,无机械损伤,遥控,不干扰粒子周围环境等优点,可以用来进行细胞分选、细胞融合、染色体切割、细胞转基因操纵、微细手术、分子马达、微小样品光谱测量等精细操作,可以广泛应用于生物医学、材料化学、纳米科技等领域. 相似文献
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《红外与毫米波学报》2018,(1)
基于光镊机理与倒置显微成像方法成功实现了铌酸锂微晶颗粒的光学捕获控制和光致取向的直接观测.由于铌酸锂微晶具有光学各向异性性质,所以在线偏振飞秒激光的操控下,所捕获的铌酸锂微晶颗粒能够依据激光偏振方向成功实现光控制取向.分析了铌酸锂微晶颗粒的激光控制取向机理,说明了铌酸锂微晶颗粒的取向可以利用激光的线性偏振方向进行光致取向旋转,有望应用于微纳光子学、MEMS、光控微型马达和微操作等科学研究领域. 相似文献
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Near-field optics: a new tool for data storage 总被引:7,自引:0,他引:7
Milster T.D. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》2000,88(9):1480-1490
Evanescent energy can be used to produce extremely small optical spots. Two practical implementations that use evanescent energy are aperture probes and solid immersion lenses (SILs). For data storage, the optical near field is defined in terms of evanescent coupling between the system used to read data and the recording layer. Because of the small spot size, near-field techniques are applied to optical data storage systems in order to increase recording density. Both aperture-type systems and SIL systems show good promise of achieving densities of more than 150 Gb/in/sup 2/. The characteristics and performance of several systems are compared, and future near-field technologies are discussed. 相似文献
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A biosensor based on single-fiber optical tweezers is proposed, which can detect the motion trajectory of cells based on the stable capture and transmission of silica microspheres as well as biological yeast cells by using a tapered optical fiber as a sensing element. The interference cavity is formed by using the fiber tip and the target particle, the detected interference signal is demodulated using Hilbert transform, and the displacement curve of the particle is plotted to realize the particle motion trajectory tracking. This method provides potential technical support for process monitoring of targeted drug delivery in biomedicine. 相似文献
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光镊具有非接触、低损伤和适用范围广等特性,被广泛应用于生命科学、纳米科技等领域。光镊系统通过调制束缚光场操控机械振子的运动,借助光动量和角动量的检测获取振子的运动状态,以实现对振子物理参量的精密测量。与传统液体光镊系统不同,真空光镊系统中的机械振子可获得与外界环境近乎完全隔离的状态,具有超高灵敏度的探测能力,是精密测量和基础物理研究的理想平台。首先介绍了真空光镊系统相关的基础理论,然后介绍了真空光镊系统的实验配置方案及其在精密测量中的典型应用,最后总结了真空光镊系统的发展现状,并给出了未来的发展建议。 相似文献
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Cicchetti R. Faraone A. Balzano Q. 《Antennas and Propagation, IEEE Transactions on》2003,51(1):89-102
A uniform asymptotic representation of the electromagnetic field radiated from arbitrary collinear array antennas is presented. The asymptotic field is obtained applying the saddle-point technique to the radiation integrals after expressing the current excited along the array axis by means of a Fourier spectral representation. The resulting electromagnetic field is expressed in terms of propagating and evanescent truncated Floquet waves (FWs). The leading asymptotic term of the FWs exhibits an optical behavior and is responsible for the slow decay of the array near-field, which can be described as cylindrical in character. The transition toward the spherical wave propagation regime is due to the interference of the cylindrical field with the relevant scattered field from the array truncations, while the reactive energy storage is due to the evanescent FWs, as well as to the progressive inductive and progressive electrostatic FWs excited close the antenna axis. Using the asymptotic field representation, prediction formulas for the spatial locations where the array near-field exhibits peak deviation from the cylindrical decay, and where the transition from cylindrical to spherical wave propagation regime takes place, have been derived. The proposed analytical technique can be adopted to analyze the spatial field distributions and the radiation mechanisms of periodic and nonperiodic linear arrays. 相似文献
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为了满足集成微波器件进行高分辨率微波近场测量的需求,本论文提出了一种基于金刚石氮空位(Nitrogen-Vacancy,NV)色心的微波近场成像技术.该技术可用于查找芯片等集成微波器件的干扰源和信号串扰.此微波近场成像方法采用金刚石NV色心颗粒作为场传感器,其中金刚石颗粒固定在锥形光纤的末端.由于塞曼效应,NV色心的光探测磁共振(Optical Detection Magnetic Resonance,ODMR)谱在外部静磁场环境中会分裂成为8个峰,通过测量共振峰频点的Rabi振荡谱,能够得到Rabi频率,接着通过2.8MHz/Gauss换算得出该处的微波场强度,最后通过将所测得所有数据点进行二维图像处理即可得到所测芯片和集成微波器件的表面微波场近场图像. 相似文献
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Borrise X. Jimenez D. Barniol N. Perez-Murano F. Aymerich X. 《Lightwave Technology, Journal of》2000,18(3):370-374
A scanning near-field optical microscope for the characterization of optical integrated devices has been developed. Compatible with a normal optical characterization setup the experimental setup allows a tapered uncoated optical fiber to scan the optical device with constant height by means of a shear force control using a tuning fork, and to obtain the evanescent field emerging from it. In this way, images showing simultaneously the topography with lateral resolution better than 10 nm and vertical resolution of 1 nm, and the optical field distribution have been obtained. Images obtained over rib waveguides show the guided mode intensity distribution, allowing characterization of the propagation of the light in the device for up to 1 mm. Identification of the guided mode propagation has been achieved by comparing the images with computer simulations. Measurement of the experimental decay lengths of the evanescent field obtained by the microscope allows a determination of the effective refractive index of the structure to be made 相似文献
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For accurate scattering computations in the far-field of flat finite objects, field based ray optical methods cannot be used directly, since the finiteness of the objects is not considered in the formulations. In this paper, planar near-field scanning techniques are used to overcome this problem. In particular, scattered ray optical fields are first computed in a scanning plane in the near-field region of the involved objects and are transformed into the far-field afterwards using field expansions in terms of spectrum density functions of outgoing waves. Since evanescent waves are avoided in the scanning plane, sampling rates less than lambda0/2 can be used for restricted angle range around the normal direction to the scanning plane. Reduced accuracy at grazing directions of observation is overcome by combining solutions provided by several scanning planes. The proposed approach is applied in the postprocessing stage of the recently developed hybrid method combining the uniform geometrical theory of diffraction with the finite element boundary integral technique and with the multilevel fast multipole method. 相似文献