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1.
李广平  高鹤  周爱  刘志海 《光子学报》2011,(10):1447-1451
基于压电换能器技术设计了一种应用于光学相干层析成像的新型内窥式二维光纤扫描探头,即利用两片压电陶瓷片和一片薄导电基片驱动光纤探头.该探头利用光纤悬臂的共振特性,通过对压电陶瓷施加等于光纤共振频率的混频信号,能同时激发光纤悬臂两正交方向上的振动,可以实现光纤悬臂的二维扫描.建立了理论模型并进行了有限元仿真分析,最后搭建了...  相似文献   

2.
用于绝对距离测量的波长扫描干涉仪信号分析   总被引:3,自引:1,他引:2  
王勇  廖延彪  田芊 《光学学报》1999,19(4):44-551
提出了一种可用于绝对距离测量的波长扫描光纤干涉仪。在时域和频域上,对其输出信号进行了研究。理论分析了法布里-珀罗腔多光束干涉所产生的干扰以及扫描过程中波长的随机漂移对输出信噪比的影响。由此提出了外腔光源结构和加工精度的要求,并设计了相应的信号处理算法,达到了距离测量所要求的0.05μm的精度和0.01μm的分辨率  相似文献   

3.
李广平  高鹤  周爱  刘志海 《光子学报》2014,40(10):1447-1451
基于压电换能器技术设计了一种应用于光学相干层析成像的新型内窥式二维光纤扫描探头,即利用两片压电陶瓷片和一片薄导电基片驱动光纤探头.该探头利用光纤悬臂的共振特性,通过对压电陶瓷施加等于光纤共振频率的混频信号,能同时激发光纤悬臂两正交方向上的振动,可以实现光纤悬臂的二维扫描.建立了理论模型并进行了有限元仿真分析,最后搭建了实验系统,验证并获得了扫描图样.实验结果实现了光纤悬臂的二维扫描,扫描范围达到(500×500)μm,调节驱动信号振幅幅值可以调节扫描范围.实验结果与理论分析和仿真相吻合,验证了方案的可行性.  相似文献   

4.
Atomic force microscopy (AFM) is typically used to measure the quantum dot shape and density formed by lattice mismatched epitaxial growth such as InAs on GaAs. However, AFM images are distorted when two dots are situated in juxtaposition with a distance less than the AFM tip width. Scanning electron Microscope (SEM) is much better in distinguishing the dot density but not the dot height. Through these measurements of the growth of InxGa1-xAs cap layer on InAs quantum dots, it was observed that the InGaAs layer neither covered the InAs quantum dots and wetting layer uniformly nor 100% phase separates into InAs and GaAs grown on InAs quantum dots and wetting layer, respectively.  相似文献   

5.
王洪喜  贾建援  赵剑 《计算物理》2006,23(3):371-374
针对主体为圆锥、尖端为球冠的扫描探针针尖物理模型,提出了针尖与试样之间等效电场分布假设,基于该假设导出了二者之间静电力的解析模型,分析了针尖结构参数与静电力间的关系.模拟计算结果和数值计算结果一致,并与相关的实验结果吻合,证实了电场分布假设的合理性.  相似文献   

6.
共焦激光扫描显微镜技术进展   总被引:5,自引:0,他引:5  
共焦激光扫描显微镜已延伸到光学显微术领域,包括共焦荧光显微镜、共焦扫描光纤显微镜、彩色共焦激光显微镜、共焦光栅光学显微镜等。并很快成为半导体材料检测和生物医学诊断的重要工具。本文对国外该显微镜技术的特性和新的进展进行了综述。  相似文献   

7.
洪海涛  俞朴  叶声华 《光学学报》2000,20(2):40-244
提出一种由定位干涉仪和测量干涉仪组成的光纤干涉绝对距离测量方法;并用标准长度光纤实现光程倍增以增大测量范围;重点讨论了用脉冲电流调制的准单色光源实现光程定位的方法及其精度。通过理论分析和仿真实验,定位重复性误差优于±1μm。  相似文献   

8.
We demonstrated a contrast enhancement in a near-field scanning optical microscope (NSOM) by optical interference with an aperture probe in reflection (illumination-collection) mode operation. We observed a NiO film deposited on a sapphire substrate and clearly visualized 2-nm-deep nano-channel structures on the surface of the film. The reflection NSOM enhanced by optical interference is quite a promising instrument for high-resolution optical detection and estimation of low-contrast nanostructures.  相似文献   

9.
李志扬  刘武  李贤芳  李兴教 《光学学报》1999,19(11):495-1503
用傅里叶角谱衍理论推导了光子扫描隧道显笛镜的标量和矢量角谱传递函数。表明,光子扫描隧道显微镜的角谱传递鲜明地分成两个区,即远场区和近场区。随首探针榈间距增大,近场区内的角谱其振幅迅速衰减,频率越高衰减越快,而相位保持不变;相反远场区内的角谱内的角谱其振幅保持不变,而相位非均匀线性均匀线性增加,频率越低增加越快。光子扫描隧道显微镜对近场角谱的采集能力是其皮瑞利衍射极限的关键。坦 步根据角谱传递函数计  相似文献   

10.
杨永斌  徐文东 《光学学报》2008,28(s2):367-372
理论上分析了静动结合的化学腐蚀法制备探针的具体机理及过程。在静态腐蚀的过程中, 利用流体力学Young-Laplace方程的一级近似解获得了光纤插入到HF酸中形成的新月形高度。在动态腐蚀过程中, 详细分析了当静态腐蚀时间和动态腐蚀时间分别取不同值时, 光纤移动速度对光纤探针结构的影响。利用此法可制备出尖端锐利、大锥角或多锥体等各种结构的光纤探针。这为实验上制备出性能优良的探针, 为拓宽扫描近场光学显微镜的应用范围奠定基础。将上述理论分析的结果与本文实验中所得初步结果进行了比较, 所得结果一致。  相似文献   

11.
在研制用于对厚的生物样品进行光学断层成像的共焦扫描荧光显微镜时,由于成像信号十分微弱及存在很强的多次散射作用,因此杂散光的抑制非常重要,而信噪比、信号背景比就成为决定能否获得高对比度、高分率图像的关键。运用光学信息量的概念,在已有的光学成像系统信息量计算、共焦扫描荧光显微镜信噪比及传递函数计算的基础上,详细分析了共焦扫描荧光显微镜信息量与信噪比等之间的定量关系。该关系表明,为了充分利用共焦扫描荧光显微镜的成像性能,必须选择适当的探测小孔。所得的结果对于共焦扫描荧光显微成像系统的研制有重要的实用价值。  相似文献   

12.
A fiber probe-based positioning scan approach was established, whose precision can reach as high as 0.8 μm. And a set of modified microscope system was designed utilizing this approach, in which the scanning probe microscope (SPM) combined with an optical microscope was manipulated. The optical microscope and scanning probe can conveniently be switched through a switch panel. The observation period of samples can significantly be shortened. And more reliable images can be provided using this approach. Our design can effectively solve the inherent disadvantages of SPM technology, which makes SPM scan and image more reliably, conveniently, safely and rapidly.  相似文献   

13.
We describe an original scanning near field optical microscope setup developed to examine rhythmically beating cardiac myocytes fully immersed in culture media. Scans could be halted at any point to record localized contraction profiles. Contractions could be detected with high sub nanometric vertical sensitivity and changed shape dramatically within adjacent sub micron-sized areas. We believe that the spatial dependency of contractions arises because of system’s ability to resolve the dynamic behavior of individual sub membrane actin bundles. Our results, combining imaging and real time recording in localized areas, reveal a new, non-invasive method for studying sub micron morphological activity in live biological samples.This paper was originally presented at the 5th International Conference on NEAR FIELD OPTICS and RELATED TECHNLOGIES (NFO-5), which was held on December 6–10, 1998 at Coganoi Bay Hotel, Shirahama, Japan, in cooperation with the Japan Society of Applied Physics and Mombusho Grant-in Aid for Scientific Research on Priority Areas “Near-Field Nano-optics” Projects, sponsored by Japan Society for the Promotion of Science.  相似文献   

14.
光子扫描隧道显微镜的探测场   总被引:1,自引:0,他引:1  
詹卫伸  郭宁 《光学学报》1996,16(10):489-1492
通过修改光子扫描隧道显微镜探测场的计算模型,推导出比较符合实际的探测场及透射系数的计算公式,并利用这一新计算公式在微机上进行了模拟计算,得到了一些过去未曾发现的现象,对光子扫描隧道显微镜的实际探测具有一定的指导意义。  相似文献   

15.
使用激光共聚焦扫描显微镜,对六种品牌和型号的激光打印机分别在打印纸和高光相纸上打印的图文墨粉厚度进行测量。结果表明,测量普通打印纸张上激光打印形成墨粉厚度时,测量数据因纸张纤维凹凸不平的影响有一定波动,相纸上激光打印形成的墨粉厚度测量数据相对稳定,并总结出随着打印文件图文线条宽度与墨粉厚度的变化规律。实验表明激光打印文件墨粉厚度的数据测量具有可行性,同一台激光打印机的打印文件墨粉厚度相对稳定,该指标作为一种重要参数可以为激光打印文件检验提供量化依据,并为打印机的同一认定提供依据。  相似文献   

16.
The feasibility of surface shape measurement by wavelength scanning interferometry was investigated by applying it to plane surfaces with various slope angles. We derived the surface height from the peak position of the Fourier transform of the interference signals arising from wavelength scanning of a dye laser at each pixel of a CCD camera, and succeeded in measuring both diffusely reflecting surfaces and machine-milled ones having slope angles up to 45°. Study of the influence of the slope angle on the standard deviations of the measured height showed that the standard deviation increases with increase of the angle of both surfaces. The increase in diffusely reflecting surfaces could be explained in terms of speckle decorrelation caused by wavelength change.  相似文献   

17.
扫描近场光学显微镜中两类光纤探针传输特性的研究   总被引:13,自引:1,他引:13  
张国平 《光学学报》1998,18(7):86-889
采用局域模式耦合理论,对扫描近场光学显微镜中的两类光纤探针-腐蚀锥和熔拉锥的传输特性进行了比较和分析。给出了光在探针锥中传输时耦合效率的分布情况,以及传输效率随锥长,针尖直径和光波长变化的特性。  相似文献   

18.
1 Introduction  Thereisanincreasingrequirementfortheprecisemeasurementofthesurfacemicrostructuresonlarge scaleobjectsofcomplexshapewithsteepsurfaceslopes .Thestylusinstrumentiswidelyusedasthepracticalmethod ,butthemeasurementaccuracyislimitedduetoitscon…  相似文献   

19.
探针尖带金属微粒的光子扫描隧道显微镜成像数值模拟   总被引:4,自引:1,他引:3  
简国树  柏菲  潘石  吴世法 《光学学报》2005,25(4):70-474
引入了色散介质的时域有限差分法散射场方程,并针对光子扫描隧道显微镜的带金属尖光纤扫描成像问题进行三维的数值模拟。在考虑了光纤和样品相互作用的情况下,采用等效入射波法设置入射波,探针扫描模式为等高扫描模式,从成像分辨力和灵敏度的角度,比较了不同入射角、不同的光纤一样品间距,不同金属类型,及不同金属尖大小的成像情况。数值模拟结果显示,带金属颗粒光纤探针尖的光子扫描隧道显微镜在成像分辨力和灵敏度上有显著的改进,而带不同类型金属颗粒情况下对分辨力影响不大,灵敏度是银最好。  相似文献   

20.
Semiconductor electronic and optoelectronic devices such as transistors, lasers, modulators, and detectors are critical to the contemporary computing and communications infrastructure. These devices have been optimized for efficiency in power consumption and speed of response. There are gaps in the detailed understanding of the internal operation of these devices. Experimental electrical and optical methods have allowed comprehensive elaboration of input–output characteristics, but do not give spatially resolved information about currents, carriers, and potentials on the nanometer scale relevant to quantum heterostructure device operation. In response, electrical scanning probe techniques have been developed and deployed to observe experimentally, with nanometric spatial resolution, two-dimensional profiles of the electrical resistance, capacitance, potential, and free carrier distribution, within actively driven devices. Experimental configurations for the most prevalent electrical probing techniques based on atomic force microscopy are illustrated with considerations for practical implementation. Interpretation of the measured quantities are presented and calibrated, demonstrating that internal quantities of device operation can be uncovered. Several application areas are examined: spreading resistance and capacitance characterization of free carriers in III-V device structures; acquisition of electric potential and field distributions of semiconductor lasers, nanocrystals, and thin films; scanning voltage analysis on diode lasers—the direct observation of the internal manifestations of current blocking breakdown in a buried heterostructure laser, the effect of current spreading inside actively biased ridge waveguide lasers, anomalously high series resistance encountered in ridge lasers—as well as in CMOS transistors; and free-carrier measurement of working lasers with scanning differential spreading techniques. Applications to emerging fields of nanotechnology and nanoelectronics are suggested.  相似文献   

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