共查询到19条相似文献,搜索用时 46 毫秒
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时间延迟积分(Time Delay Integration,TDI)图像传感器具有高速、高灵敏度等特点,广泛应用于高通量、大视场的荧光显微成像系统中.显微物镜视场内响应均匀是精确获取荧光能量分布的基础,为提高系统成像质量和测量准确度,研究了适用于TDI荧光显微成像系统的平场校正或响应非均匀性校正方法.根据TDI荧光成像... 相似文献
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现在生物芯片(微阵列)的检测一般是基于扫描成像分析技术,这种方法在需要平行快速检测的应用中成像速度受到限制。我们设计搭建了一套检测生物芯片一次成像装置,其原理示意图如图1所示。 相似文献
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美国的Minsky在20世纪50年代末提出共焦显微术的概念以来,尽管共焦显微术可以获得更高的分辨率,但不仅成像速度慢,而且需要使用光电增强器对采集光点信号进行增强,导致制造成本过高,所以除一些成像质量要求极高的显微系统外,其他的显微系统很少应用。讨论了线结构光共焦显微术的原理、优缺点以及影响性能的几个重要因素,并介绍其最新的研究状况。 相似文献
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G. J. Brakenhoff H. T. M. van der Voort E. A. van Spronsen N. Nanninga 《Journal of microscopy》1989,153(2):151-159
The improved resolution and sectioning capability of a confocal microscope make it an ideal instrument for extracting three-dimensional information especially from extended biological specimens. The imaging properties, also with finite detection pinholes are considered and a number of biological applications demonstrated. 相似文献
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We report on a chromatic axial scanning method for two-photon excitation fluorescence imaging. Effective axial scanning is achieved by incorporating a Fresnel lens in the system, which has large chromatic aberration and can therefore focus the excitation beam to different axial positions depending on its wavelength. We experimentally demonstrated this technique and used it to image the cross-section of fluorescent microspheres. 相似文献
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An inverted fluorescence microscope was upgraded into a compact three-dimensional laser scanning microscope (LSM) of 65 x 62 x 48 cm dimensions by means of a fast kHz galvoscanner unit, a piezodriven z-stage, and a picosecond (ps) 50 MHz laser diode at 405 nm. In addition, compact turn-key near infrared femtosecond lasers have been employed to perform multiphoton fluorescence and second harmonic generation (SHG) microscopy. To expand the features of the compact LSM, a time-correlated single photon counting unit as well as a Sagnac interferometer have been added to realize fluorescence lifetime imaging (FLIM) and spectral imaging. Using this unique five-dimensional microscope, TauMap, single-photon excited (SPE), and two-photon excited (TPE) cellular fluorescence as well as intratissue autofluorescence of water plant leaves have been investigated with submicron spatial resolution, <270 ps temporal resolution, and 10 nm spectral resolution. 相似文献
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We develop a multidimensional fluorescence imaging technique by implementing a wide-field time-gated fluorescence lifetime imaging into digital scanned laser light-sheet microscopy (FLIM-DSLM) to measure 3D fluorescence lifetime distribution in mesoscopic specimens with high resolution. This is achieved by acquiring a series of time-gated images at different relative time delays with respect of excitation pulses at different depths. The lifetime is determined for each voxel by iteratively fitting to single exponential decay. The performance of the developed system is evaluated with the measurements of a lifetime reference Rhodamine 6G solution and a subresolution fluorescent bead phantom. We also demonstrate the application performances of this system to ex vivo and in vivo imaging of Tg(kdrl:EGFP) transgenic zebrafish embryos, illustrating the lifetime differences between the GFP signal and the autofluorescence signal. The results show that FLIM-DSLM can be used for sample size up to a few millimetres and can be utilised as a powerful and robust method for biomedical research, for example as a readout of protein–protein interactions via Förster resonance energy transfer. 相似文献
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M. J. Cole J. Siegel S. E. D. Webb R. Jones K. Dowling M. J. Dayel D. Parsons-Karavassilis P. M. W. French M. J. Lever† L. O. D. Sucharov‡ M. A. A. Neil‡ R. Jukaitis‡ & T. Wilson‡ 《Journal of microscopy》2001,203(3):246-257
A whole-field time-domain fluorescence lifetime imaging (FLIM) microscope with the capability to perform optical sectioning is described. The excitation source is a mode-locked Ti:Sapphire laser that is regeneratively amplified and frequency doubled to 415 nm. Time-gated fluorescence intensity images at increasing delays after excitation are acquired using a gated microchannel plate image intensifier combined with an intensified CCD camera. By fitting a single or multiple exponential decay to each pixel in the field of view of the time-gated images, 2-D FLIM maps are obtained for each component of the fluorescence lifetime. This FLIM instrument was demonstrated to exhibit a temporal discrimination of better than 10 ps. It has been applied to chemically specific imaging, quantitative imaging of concentration ratios of mixed fluorophores and quantitative imaging of perturbations to fluorophore environment. Initially, standard fluorescent dyes were studied and then this FLIM microscope was applied to the imaging of biological tissue, successfully contrasting different tissues and different states of tissue using autofluorescence. To demonstrate the potential for real-world applications, the FLIM microscope has been configured using potentially compact, portable and low cost all-solid-state diode-pumped laser technology. Whole-field FLIM with optical sectioning (3D FLIM) has been realized using a structured illumination technique. 相似文献
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The imaging performance in single-photon (1-p) and two-photon (2-p) fluorescence microscopy is described. Both confocal and conventional systems are compared in terms of the three-dimensional (3-D) point spread function and the 3-D optical transfer function. Images of fluorescent sharp edges and layers are modelled, giving resolution in transverse and axial directions. A comparison of the imaging properties is also given for a 4Pi confocal system. Confocal 2-p 4Pi fluorescence microscopy gives the best axial resolution in the sense that its 3-D optical transfer function has the strongest response along the axial direction. 相似文献
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Two-photon fluorescence lifetime imaging microscopy of macrophage-mediated antigen processing 总被引:2,自引:0,他引:2
T. French P. T. C. So D. J. Weaver Jr T. Coelho-Sampaio E. Gratton E. W. Voss Jr & J. Carrero 《Journal of microscopy》1997,185(3):339-353
Two-photon fluorescence lifetime imaging microscopy was used noninvasively to monitor a fluorescent antigen during macrophage-mediated endocytosis, intracellular vacuolar encapsulation, and protease-dependent processing. Fluorescein-conjugated bovine serum albumin (FITC–BSA) served as the soluble exogenous antigen. As a relatively nonfluorescent probe in the native state, the antigen was designed to reflect sequential intracellular antigen processing events through time-dependent changes in fluorescence properties. Using two-photon lifetime imaging microscopy, antigen processing events were monitored continuously for several hours. During this time, the initial fluorescein fluorescence lifetime of 0.5 ns increased to α 3.0 ns. Control experiments using fluorescein conjugated poly- l -lysine and poly- d -lysine demonstrated that the increase in fluorescence parameters observed with FITC–BSA were due to intracellular proteolysis since addition of the inert d -isomer did not promote an increase in fluorescence lifetime or intensity. Comparisons of intravacuolar and extracellular FITC–dextran concentration suggested active localization of dextran in the vacuoles by the macrophage. In addition, the kinetics of degradation observed using two-photon microscopy were similar to results obtained on the flow cytometer, thus validating the use of flow cytometry for future studies. 相似文献
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D.K. BIRD A.L. SCHNEIDER† A.C. WATKINSON‡ B. FINNIN† & T.A. SMITH 《Journal of microscopy》2008,230(1):61-69
We demonstrate the potential of fluorescence lifetime imaging by time-correlated single-photon counting as a method for monitoring the transdermal diffusion pathway and diffusion rate of pharmaceuticals in human skin. The current application relies on observing subtle changes in the fluorescence lifetime of the intrinsic fluorophores present in the intracellular region between corneocytes of the stratum corneum. We have comprehensively characterized the measured fluorescence lifetimes from intracorneocyte junctions in three skin section types (dermatomed skin, epidermal membranes and stratum corneum) revealing statistically significant differences of the short lifetime component between each of the types, which we attribute to the sample preparation and imaging method. We show using epidermal membrane sections that application of a drug/solvent formulation consisting of ethinyl estradiol and spectroscopic grade ethanol to the surface gives rise to a slight but statistically significant shortening of the fluorescence lifetime of the long-lived emitting species present in the sample, from approximately 2.8 ns to 2.5 ns. The method may be useful for future studies where the kinetics and pathways of a variety of applied formulations could be investigated. 相似文献