基于布拉格反射镜的X射线多色单能成像谱仪

报道了一种基于布拉格反射镜的多色单能成像谱仪研制工作,谱仪由针孔阵列、布拉格反射镜和CCD相机组成.大约有300个微孔的针孔阵列板置于布拉格镜前用于空间成像,通过布拉格反射镜的单色化,投射到CCD上的数百个小孔成像沿色散方向获得了能量分辨.经过图像处理,可以还原得到目标的多色单能二维成像.根据采用的布拉格分光元件和图像还原方法,谱仪的能量分辨达到了50—200（λ/Δλ）;针孔成像的空间分辨优于10 μm.同时还为该谱仪开发了专门的单能图像重建软件及图像数据后处理软件,可以在任意选择的窄能带内还原准单能图像.并重点介绍了该谱仪的优化设计、获得的技术指标以及专门研制的超短周期（2.5 nm）X射线W/B₄C多层镜. 关键词： X射线光学 诊断技术 布拉格反射镜 X射线多层镜     

An application of the electron mirror in the time-of-flight spectrometer

We suggest applying of the spherical electron mirror in the time-of-flight electron spectrometer with a position sensitive detector in order to increase the effective acceptance solid angle of the spectrometer. The spherical electron mirror is placed near the specimen and it focuses electrons on a position sensitive detector as a converging electron flux. The electron mirror increases the acceptance angle of the spectrometer by a factor of 20. The electron mirror of the spectrometer consists of an inner spherical electrode of the radius R and an outer spherical electrode of the radius 1.1R. The central segment of the inner electrode inside the linear angle of 80° is made of a grid. The detector plate radius is about 0.23R. The acceptance solid angle of the spectrometer with this electron mirror is about 1.1sr, the range of the polar angle of emission is 20°–90° relative to the surface normal, and the range of the azimuth angle of emission at its maximum is ±36° relative to the basic plane of the spectrometer. The design of the spectrometer allows to recover the electron trajectory for each detected electron and to calculate the energy and the emission angle of the electron. The energy resolution of the spectrometer is about 0.2 eV/ns for the electron energy of 10 eV. The energy range is from E_min0.1eU_r up to eU_r, where U_r is the retarding potential of the electron mirror. The perturbing influence of the grid of the electron mirror limits mainly the angular resolution of the spectrometer and affects relatively slightly the energy resolution. The electron spectrometer with two detectors and two electron mirrors symmetric about the spectrometer axis allows to measure electron pairs in coincidence in a wide range of emission angles and energies with k-resolutions.     

基于MEMS微镜的长波近红外光谱仪的设计与实现

为适应光谱仪微型化、集成化的发展趋势,详细分析了MEMS微镜应用于微型长波近红外光谱仪的方法和涉及的主要问题,例如分光系统的设计、MEMS微镜的选择、探测器与前置放大电路的设计等。并将50 Hz谐振频率、峰峰驱动电压为10V的MEMS微镜、高灵敏度的InGaAs单元探测器,结合立特罗式分光光路,设计和实现了900～2 055 nm波段的微型长波近红外光谱仪样机,其中1 000～1 965 nm谱段的光谱分辨率介于9.4～16 nm之间。采用MEMS扫描微镜技术后,一方面简化了光谱仪中的复杂机械结构,使尺寸可以更小;另一方面实现了单探测器的长波近红外光谱仪,与阵列长波近红外探测器光谱仪相比,成本有所降低。作为应用实例,此样机成功对纯水以及乙醇-水溶液的长波近红外光谱进行了测量,实现了乙醇-水溶液的浓度预测分析,其中本样机测量的纯水长波近红外光谱与文献相符。     

MOEMS微镜面阵光谱仪的优化设计与实验

MOEMS(micro optical electronic mechanical system)微镜面阵光谱仪主要利用微镜面阵分时选通实现单个探测器光谱测量,具有无需斩波器实现脉冲信号输出,无需机械模板实现哈达吗调制,象元分辨率高,体积小,成本低等优点.针对MOEMS微镜面阵光谱仪设计中,狭缝尺寸与光通最之间的矛盾,...     

一种时间分辨三通道软X射线光谱仪

报道了时间分辨的三通道软X射线光谱仪研制工作，重点介绍了研制的三通道能谱仪的工作原理以及210 eV，420 eV和900 eV三个能区的设计参数，谱仪在上海神光Ⅱ高功率激光器三倍频实验中进行了多次实时考核，取得较好实验结果，将多道平面镜、滤光片成功配接于高时间分辨X射线条纹相机上，使该谱仪在亚千电子伏能区内，可同时进行三个波段软X射线的时间和空间分辨测量，提供的实验结果也表明：X射线平面镜结合滤光片的分光技术可应用于高时间分辨的X射线条纹相机上，从而获得高达10 ps的时间分辨. 关键词： 软X射线条纹相机 平面镜 滤光片 掠入射     

振镜法测量等离子体离子温度

 离子温度是托卡马克等离子体一个重要参数，介绍了一套振镜扫描装置，该装置主要由0.5m单色仪和安装在出射狭缝前的振动的石英镜片组成，时间分辨率小于10ms，系统测量误差小于20eV。测量了HT-6M托卡马克CV(227.1nm)谱线的线形，并由谱线的多普勒展宽得出欧姆加热和离子回旋共振加热（ICRH）下的离子温度，结果表明ICRH期间离子温度由200eV升高到300eV。这套装置广泛应用在中小型托卡马克上。     

改进型Czerny-Turner成像光谱仪光学系统设计方法

像散是目前影响Czerny-Turner结构成像光谱仪空间分辨率最大的像差。首先引入柱面反射镜,利用光焦度衡量像散大小,推导出易于计算的像散校正公式,有效地校正了像散。给出准直镜到光栅距离的计算方法,有效校正了成像光谱仪边缘视场像差。给出了成像光谱仪像面倾角的计算方法,实现了宽波段的像差校正。最终利用上述方法设计了一套用于115～200nm的改进型Czerny-Turner成像光谱仪,焦距f′=48mm,F数为5.0,全视场、全波段调制传递函数(MTF)在0.7以上。全波段光谱分辨率为0.22nm,像面大小为8mm×7mm。设计方法适用于多种结构要求的成像光谱仪。     

Adsorption of aniline on silver mirror studied by surface‐enhanced Raman scattering spectroscopy and density functional theory calculations

The adsorption of aniline on a silver mirror was studied by surface‐enhanced Raman scattering (SERS) spectroscopy and density functional theory (DFT) calculation methods. The normal Raman and SERS spectra of pure aniline liquid and its solutions were recorded by a micro‐Raman spectrometer with excitation at 514.5 nm. Orientation of the aniline molecule adsorbed on the Ag mirror is discussed. The results indicate that pure aniline is adsorbed on the surface of the Ag mirror with a tilted orientation. The conformer with the nitrogen atom interacting with the metal surface would be dominant. DFT calculations further confirm the experimental results that charge transfer (CT) takes place from the highest occupied molecular orbital(HOMO) of aniline to the singly occupied molecular orbital (SOMO) of the silver surface. In this paper, the frontier molecular orbital theory has been successfully used to explore the interaction between the aniline molecule and the silver surface. Copyright © 2011 John Wiley & Sons, Ltd.     

Synchrotron X‐ray tests of an L‐shaped laterally graded multilayer mirror for the analyzer system of the ultra‐high‐resolution IXS spectrometer at NSLS‐II

Characterization and testing of an L‐shaped laterally graded multilayer mirror are presented. This mirror is designed as a two‐dimensional collimating optics for the analyzer system of the ultra‐high‐resolution inelastic X‐ray scattering (IXS) spectrometer at National Synchrotron Light Source II (NSLS‐II). The characterization includes point‐to‐point reflectivity measurements, lattice parameter determination and mirror metrology (figure, slope error and roughness). The synchrotron X‐ray test of the mirror was carried out reversely as a focusing device. The results show that the L‐shaped laterally graded multilayer mirror is suitable to be used, with high efficiency, for the analyzer system of the IXS spectrometer at NSLS‐II.     

太阳极紫外成像光谱仪光学系统设计

在极紫外波段对太阳进行超光谱成像观测是研究太阳上层大气,日冕中等离子物理特性的重要手段。依据太阳极紫外成像光谱仪的应用,结合国内外极紫外成像光谱仪发展现状,制定了太阳极紫外成像光谱仪的性能指标。通过比较各种光学结构的优缺点,选择望远镜与光谱仪组合的结构。讨论并选择了可用的基本元器件,望远系统采用离轴抛物面反射镜,分光器件为高密度超环面等间距光栅。设计出符合指标的光学系统。最后给出了太阳极紫外成像光谱仪的设计过程、详细参数与结果。光学系统的工作波段为17.0～21.0nm,视场是1 228″×1 024″,空间分辨率达到0.8arcsec.pixel-1,光谱分辨率约为0.001 98nm.pixel-1,系统总长度约为2.8m。