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21.
《Surface and interface analysis : SIA》2003,35(3):282-286
We have developed a high‐speed image processing CCD video camera for real‐time energy‐loss imaging using a conventional electron microscope with an energy‐loss imaging facility. As an initial demonstration of real‐time lock‐in energy‐loss imaging, a background‐subtracted energy‐loss image was observed by attaching the high‐speed image processing CCD video camera to an analytical electron microscope equipped with a floating‐type energy‐loss imaging analyser. Copyright © 2003 John Wiley & Sons, Ltd. 相似文献
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The acquisition of images with different modalities may involve different alterations with respect to an ideal model. Inhomogeneous brightness and contrast, blur due to non-ideal focusing, distortions are common. It is proposed herein to account for such effects for instance by registering a calibration target image with an actual optical image to measure lens distortions. An Integrated Digital Image Correlation (I-DIC) algorithm is proposed to account for the above artifacts and the algorithm is detailed. The resolution and uncertainty of the technique are first investigated on synthetic images, and then applied to the measurement of distortions for infrared (IR) images. The procedure is shown to reduce drastically the residual level assessing the validity of the image formation model, but more importantly allowing for a much improved registration of images. 相似文献
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The characteristic X-ray detector (CXRD), a CsI(Tl) scintillator with a 50-mm diameter, is a directional X-ray sensor that measures characteristic X-rays from radioactive material, such as 137Cs, and identifies the direction of radioactive contamination. We evaluated a CXRD and visualized the distribution of radioactivity in the contaminated area near the Fukushima Dai-ichi nuclear power station, where the ambient dose equivalent rate was 2.1 μSv/h at 1 m above ground level. We found a good correlation between the characteristic X-ray fluxes and the distribution of radioactive contaminants with a 0.823 Pearson product–moment correlation coefficient. 相似文献
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The fundamental property of radially polarized terahertz radiation, which is axial symmetry of the polarization state in the radial direction, was measured with a Schottky diode detector and with a terahertz camera and wire-grid linear polarizer. Radially polarized terahertz radiation was generated from coherent transition radiation using a 30-MeV sub-picosecond electron beam. Bow-tie intensity distributions, aligned along the polarization direction, were clearly observed with the terahertz camera and could be rotated by changing the direction of the linear polarizer. The measured intensity distribution agreed with the calculated value. A video of the data can be found online. 相似文献
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In this work, the optical absorption and thermal properties of polyimide aerogel have been investigated by Infrared Camera, ultraviolet–visible and photoacoustic spectroscopy under low energy proton irradiation. The characterization method of the infrared camera can obtain the optical absorption ratio, and meanwhile get the information of specific heat capacity. Moreover, it can acquire the nature information of damaged area rather than the overall performance. The results show an increase in optical absorption after proton irradiation, which is in good coincidence with Ultraviolet–visible spectroscopy analysis. And the specific heat capacity decreased linearly with proton fluences, which can be attributed to the irradiation damage and carbonization in polyimide aerogel. The Raman spectra suggested the cleavage of chemical bonds and carbonization in polyimide aerogel. This work provides the novel, non-destructive and sensitive methods to characterize irradiation damage of aerogel. 相似文献
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应用数码照相技术分析塞曼分裂图谱 总被引:1,自引:0,他引:1
讨论了现有塞曼效应实验成像方法的不足;介绍一种用普通数码照相机进行拍摄和计算机程序处理技术研究塞曼效应的方法. 相似文献
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建立了一台基于新研制的高重复频率皮秒扫描相机的双光子激发荧光寿命显微成像系统,重点介绍所研制的高重复频率皮秒扫描相机。为了在高时间分辨力的同时扩大时间测量范围,实现大面积两维空间高时间分辨取样测量,从而提高采样速率和更有效地发挥扫描相机的作用,设计和研制了一种大面积、高时间分辨力扫描变像管和一种重复频率高达1MHz的斜坡电压扫描电路。基于上述关键部件所研制的扫描相机具有重复频率高、扫描速度可调、时间分辨力高、工作面积大、非线性低、触发晃动小等优点。用钛宝石飞秒激光器作为激光脉冲源,通过脉冲提取器将76MHz的高重复频率降低为1MHz,采用可调延时器和标准具对扫描相机的时间分辨力、扫描速度和非线性进行标定。该系统的时间分辨力达到6.5ps,非线性为2.60%,可测量的时间范围从十几皮秒到几十纳秒。测量了若丹明6G和香豆素314两种标准荧光染料的荧光寿命,取得了与参考文献一致的实验结果。 相似文献