共查询到20条相似文献,搜索用时 46 毫秒
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采用显微激光共焦拉曼散射光谱扫描系统对活态红细胞进行拉曼光谱(点测定、线扫描、二维扫描)测定及成像的技术与方法进行了研究,并对514 nm激光对红细胞在拉曼扫描中的影响进行了评价。通过扫描前后细胞的拉曼光谱变化和亮场图像变化确定了在不同扫描模式下既可获得较好的拉曼散射信号,又不会影响细胞生命活动与功能的合适扫描参数的设置。对于点扫描模式,样品激光功率是重点调节的参数,一般应小于1.5 mW。对于线扫描模式,照射激光功率和扫描间隔(步进)是要重点关注的参数。小扫描间隔意味着激光能量相对聚集,易对细胞造成损伤;大扫描间隔可以较好地降低激光对细胞的损伤,但是空间分辨率会因此而下降。对于线扫描,建议扫描间隔大于0.5 μm、照射激光功率小于0.7 mW。对于二维扫描,除照射激光功率、扫描间隔需要调节外,其他扫描参数也要作相应调节以降低激光对红细胞的影响,可适当降低样品温度和增加共焦孔径尺寸降低二维扫描过程中激光对红细胞的影响。1.0 μm扫描间隔、0.7 mW的照射激光功率和500 μm共焦孔径,以及样品温度适当调低可得到较好的二维红细胞拉曼图像。对于所有扫描模式,如果得到的红细胞的拉曼信号足够强,也可适当降低曝光积分时间以降低激光对红细胞的影响。实验前进行实验过程的优化对活态细胞的拉曼测试也非常重要。 相似文献
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本文探讨一种使用单模光纤同时作为点源与点探测器的激光共焦扫描显微系统。该系统具有与传统共焦扫描相同的功能,但更容易操作,结构更简单,系统更稳定,文中给出系统的原理设计方案,并对其光学特性进行分析。 相似文献
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利用共焦扫描显微术和变迹术相结合实现光学超分辨 总被引:2,自引:0,他引:2
运用适当形式匠光瞳滤波器民成像系统点振响应的分布,歙 具心于冲击函数的形式,这样就有可能实现光学超分辨,但变迹术的运用往往会因其强烈的旁瓣效应而导致成像系统对比度的急剧下降。本文提出的共焦型超分辨方案则能有效地抑制上述旁瓣。此外,本文学进一瞠提出了实现三维光学超分辨手理论框轲。 相似文献
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往复式逐行扫描是一种提高激光共焦扫描显微成像帧速的有效方式,然而随着帧速的提高,这种扫描方式在图像重构时会带来更严重的图像错位。根据高速振镜运动特性,分析了激光共焦高速扫描显微成像系统逐行扫描下的重构图像错位原理,设计了基于形态学梯度的重构图像错位评价算法,并且结合搜索错位评价最小点的单目标约束粒子群算法实现了重构图像错位校正。经实验验证,该算法适用于成像帧速高达300 frame/s的重构图像错位校正;与未进行错位校正的图像相比,校正后的成像分辨率提高了68.83%,同时该算法能够适用于不同振镜搭配方式和不同扫描帧速的图像重构。 相似文献
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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
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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
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We have developed laser printer optics using various kinds of multiple beam generation devices, such as a polarization prism, grating, diode laser array, and optical fiber array. Recently we successfully demonstrated laser-print experiments using five beams from an optical fiber array. In the array, fibers are arranged with a spacing of 0.15 mm and emit circular Gaussian beams that have a diameter of 5 μm and a wavelength of 635 nm. The wavelength of diode lasers is determined from sensitivity of the photoconductor drum of As2Se3 material. The arrangement error vertical to the array is mostly suppressed below 0.4 μm. In the optics, curve of scan lines and print position errors in the scan direction are suppressed to a negligible size due to minimization of the magnification variation in the sub-scan direction along the print width and achromatized design, respectively.This paper was originally presented at the 2nd International Conference on Optical Design and Fabrication, ODF2000 which was held on November 15-17, 2000 at the International Conference Center, Tokyo, Waseda University, Japan. 相似文献
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体视学是由形态学与数学交叉形成的一门新兴学科,通过二维结构信息定量测量和分析三维形态结构特征。采用体视学点计数方法,对肿瘤细胞B16F10、B16/Vector及B16/GPR4各20组的共聚焦显微镜图像进行测量,定量分析了其三维形态参数的差异。对比三类细胞的体视学参数发现,对照组B16/Vector和原始细胞B16F10没有明显差异,实验组B16/GPR4的细胞比表面及相对形状因子参数与另两类细胞相比均表现出了显著性差异(p值分别小于0.05和0.02,即B16/GPR4细胞形态光滑,没有较多的突触和伪足),与前期Transwell小室细胞侵袭及迁移实验研究结果相吻合,体现出B16/GPR4细胞中G蛋白耦联受体4(GPR4)基因对细胞迁移性抑制的生物特性。研究结果表明,体视学和激光扫描共聚焦显微镜细胞图像的结合,可以实现细胞三维结构参数的快速测量,是细胞生物学尤其是细胞形态学分析的有效研究方法。 相似文献
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A simple method to determine the thermal focal length of LD end-pumped solid-state laser with stable resonator is presented. The M2 factor describing the quality of the beam can be obtained by scanning a slit through the multi-mode Gaussian beam field. The waist width of the beam and the corresponding TEM00 under the same parameters of laser are then deduced through the law of multi-mode Gaussian beam propagation. Based on the standard matrix theory of stable resonator, the thermal focal length of the gain medium can be easily achieved. To show the application of this approach, the thermal focal length of an LD pumped Nd:YVO4 laser is measured and the experimental results are in agreement with the theoretical prediction. 相似文献
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Rachel Quarrell Timothy D. W. Claridge George W. Weaver Gordon Lowe 《Molecular diversity》1996,1(4):223-232
Summary In view of the widespread use of TentaGel resin beads for the synthesis of combinatorial libraries, the properties of TentaGel resin have been examined using a combination of confocal laser microscopy and NMR spectroscopy. Evidence is presented that trypsin, a 23.5-kDa enzyme, can penetrate to the core of 90-m TentaGel beads, and that the matrix of such beads permits molecular motion at a similar rate to that in solution. The beads act as a separate gel phase rather than as a porous solid. These conclusions have important implications for the bioassay of on-bead combinatorial chemical libraries. 相似文献
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T.A. Melnychuk 《Applied Surface Science》2007,254(4):1002-1006
Trends of structural modifications and phase composition occurring in In4Se3 thin films and In4Se3-In4Te3 epitaxial heterojunctions under laser irradiations have been investigated. Dynamics of the layer structure modification, depending on laser modes, i.e. pulse duration τ = 2-4 ms, irradiation intensity I0 = 10-50 kW/cm2, number of pulses N = 5-50, was studied by electron microscopy. An increase in laser influence promotes enlargement of the layer grains and transformation of their polycrystalline structure towards higher degree of stoichiometry. As a result of laser solid restructuring heterojunctions of In4Se3-In4Te3, being photosensitive within 1.0-2.0 μm and showing fast time of response, have been obtained. Laser modification of structure enables one to optimize electrical and optical properties of functional elements on the base of thin films and layers of In4Se3, In4Te3, widely used as infrared detectors and filters. 相似文献
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Bikram Nath 《Molecular physics》2014,112(16):2085-2092
We have designed and optimised a combined laser pulse using optimal control theory-based adaptive simulated annealing technique for selective vibrational excitations and photo-dissociation. Since proper choice of pulses for specific excitation and dissociation phenomena is very difficult, we have designed a linearly combined pulse for such processes and optimised the different parameters involved in those pulses so that we can get an efficient combined pulse. The technique makes us free from choosing any arbitrary type of pulses and makes a ground to check their suitability. We have also emphasised on how we can improve the performance of simulated annealing technique by introducing an adaptive step length of the different variables during the optimisation processes. We have also pointed out on how we can choose the initial temperature for the optimisation process by introducing heating/cooling step to reduce the annealing steps so that the method becomes cost effective. 相似文献
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A novel use of confocal laser scanning microscopy (CLSM) makes the truly focused field-of-view with well-defined depthwise resolution possible for microscale particle image velocimetry (μ-PIV) applications. The operating principle of the CLSM is presented using the point spread function (PSF) that describes diffracted images of extremely small particles. The implemented high-speed CLSM system using a Nipkow rotating disk is applied to measure the microscale rotating Couette flow field confined between two parallel horizontal disks that are 180-μm apart, with the bottom one stationary and the top one rotating and seeded by 200-nm fluorescent spheres. The CLSM provides much distinct particle images in comparison with the conventional wide-field microscopy (WFM) and the measured vector profiles are more concentric and accurate depicting closer to an ideal Couette flow. 相似文献