扫描电镜中象散的消除

文章强调象散是影响图象清晰度的重要因素,消除象散是扫描电镜(SEM)工作中重要而较难掌握的一环;介绍了象散的产生、消象散器的工作原理及象散消除过程。     

《科学仪器光谱全谱仪的研制与开发》课题中的部分成果

1、台式光谱全谱仪本项目是国家科技部十五攻关项目《光谱仪器的研制与开发》课题中的《光谱全谱仪》子课题的研究内容之一。台式光谱全谱仪是一种采用线阵CCD接收器,快速电控扫描的台式光谱全谱仪-即快速紫外可见分光光度计。系统由光度计主机、光源、样品测量等组成,可独立完成光谱扫描、光度测量及峰值捡出等功能。可根据市场需求扩充其它附件及功能。仪器采用先进的平场凹面光栅作为分光器件,NMOS线性图象传感器作为接收器,可同时测量190 - 110 0nm的全波段光谱,最短测量时间0 .1S。通过RS2 32与微机通讯,由UVWin5 .0软件读取测量…     

存稿文摘

象散和球面反射镜本文叙述的象散分析是根据H·Coddington在十九世纪初发现了的一系列方程进行的。这些方程描绘出“闭合”(微分)弧矢和子午光线周围主光线通过一个光学成象系统确定象散和场曲率的方法。图5。     

全息凹面光栅单色仪的研讨

传统的凹面光栅单色仪由于其象散过大，使能量受到影响而在某些场合失去了可用性。全息消象差凹面光栅改善了象散对能量的影响，使凹面光栅单色仪焕发新的生机。笔者对全息消象差凹面光栅进行了较为细致的观察、分析、计算，以更深一步地了解全息消象差凹面光栅的性能特点，并与经典的濑谷－波冈装置进行了比较。最后，对几个与凹面光栅单色仪有关的问题也进行了探讨。     

全息凹面光栅单色仪的研讨

传统的凹面光栅单色仪由于其象散过大，使能量受到影响而在某些场合失去了可用性。全息消象差凹面光栅改善了象散对能量的影响，使凹面光栅单色仪焕发新的生机。笔者对全息消象差凹面光栅进行了较为细致的观察、分析、计算，以更深一步地了解全息消象差凹面光栅的性能特点，并与经典的獭谷-波冈装置进行了比较。最后，对几个与凹面光栅单色仪有关的问题也进行了探讨。     

基于FPGA的微型光谱仪CCD系统设计

论述了一种基于FPGA的高灵敏度的CCD光谱仪检测系统设计方案和实现方法.该设计方案采用平场凹面光栅为光学系统,以FPGA为主控芯片,由A/D芯片完成对CCD输出信号的模数转换.采用FPGA实现对CCD的时序和A/D转换时序的驱动,然后通过USB与上位机进行通信,实现实时光谱数据的采集、传输与显示.实验结果表明,该系统...     

SDHR—1000全息凹面光栅双单色仪

本文介绍一种使用Ⅱ型消象散一慧差全息凹面光栅的双单色仪,简述了仪器的原理、结构、特点及用途,介绍了仪器的主要指标和性能测试,给出了实际应用结果。     

掠入射消象差光栅谱仪的调试

本文介绍了在对原谱仪的部分非真空接口、快门等结构进行改进的基础上,对掠入射消象差光栅谱仪进行全面调试和相谱的方法,并得出了结果。     

傅里叶变换近红外光谱进展

本文报道了近红外光谱原理、特点、FT—NIR光谱仪发展趋势和近红外光谱分析方法及应用实例。     

同轴型非对称场离子迁移谱仪分离与聚焦原理的数学模型

同轴型非对称场离子迁移谱仪能在室温、大气压条件下对离子混合物进行快速分离和聚焦,是一种新的分离方法.本文以简单的数学模型说明同轴型非对称场离子迁移谱仪的分离与聚焦原理.模型结论表明,非对称场离子迁移谱仪的分离聚焦效果与驱散电压、非对称场电源的频率、同轴圆筒的结构及离子的种类等因素有关.该模型以文献报道数据为基础,模型的结论与文献报道实验结果符合较好.     

One-dimensional space resolving flat-field holographic grating soft x-ray framing camera spectrograph for laser plasma diagnostics

A 1D space resolving x-ray spectrum diagnostic system has been developed to study the radiation opacity of hot plasma on SG-II laser facility. The diagnostic system consists of a 2400 lines/mm flat-field holographic grating and a gated microchannel plate coupled with an optical CCD and covers the wavelength range of 5-50 A?. The holographic grating was compared with a ruled one by measuring the emission spectra from a laser-produced molybdenum plasma. The results indicate that the holographic grating possesses better sensitivity than the ruled grating having nearly similar spectral resolution. The spectrograph has been used in radiative opacity measurement of Fe plasma. Simultaneous measurements of the backlight source and the transmission spectrum in appointed time range in one shot have been accomplished successfully with the holographic grating spectrometer. The 2p-3d transition absorption of Fe plasma near 15.5 A? in has been observed clearly.     

一种用于激光等离子体研究的掠入射光栅谱仪

介绍一种结构新颖的研究Ｘ激光的关键诊断仪器──掠入射光栅谱仪的研制。掠入射光栅摄谱系统由三部份组成：掠入射光栅谱议、四维精密微调装置和一个带光纤传象束、摄象机、监示器和激光准直仪等构成的瞄准系统。文中论述了掠入射光栅谱仪的光路设计、机电结构设计特点和性能实验结果。     

A novel facility for ageing materials with narrow-band ultraviolet radiation exposure

A facility for exploring wavelength dependencies in ultraviolet (UV) radiation induced degradation in materials has been designed and constructed. The device is essentially a spectrograph separating light from a lamp to spectrally resolved UV radiation. It is based on a 1 kW xenon lamp and a flat-field concave holographic grating 10 cm in diameter. Radiation at the wavelength range 250-500 nm is dispersed onto the sample plane of 1.5 cm in height and 21 cm in width. The optical performance of the device has been characterized by radiometric measurements. Using the facility, test samples prepared of regular newspaper have been irradiated from 1 to 8 h. Color changes on the different locations of the aged samples have been quantified by color measurements. Yellowness indices computed from the color measurements demonstrate the capability of the facility in revealing wavelength dependencies of the material property changes in reasonable time frames.     

XUV掠入射光栅摄谱仪的设计与研制

文章介绍了XUV掠入射光栅摄谱仪的光学原理、结构特点,工艺、材料选择及部分实验结果。     

全息凹面光栅平场摄谱仪的光学设计及像差优化研究

本文利用全息凹面光栅像差理论,提出了全息凹面光栅平场摄谱仪的光学设计方法,推导了在平场像面获得评价像质的点列图分布的计算公式。以波像差系数的平方和为评价函数,对全息凹面光栅的光学参量进行了优化设计,并建立了相应的平场摄谱仪设计程序软件。     

平面光栅摄谱仪改造为光电直读光谱仪

照相式的光栅摄谱仪常用电弧光源、相板照相、洗相及测黑度等进行发射光谱分析。我们用ICP光源、光电转换、精密机械传动、电子技术及计算机控制和数据处理等新技术,将摄谱仪改造升级为高性能ICP扫描直读光谱仪。此仪器适用于光谱定量分析、光谱分析研究和光谱教学。     

Grazing incidence spectrograph-monochromator for xuv spectroscopy in the 5-900 A region

A combination grazing incidence spectrograph for photographic recording and scanning monochromator has been realized. The instrument is of a modular concept and all the internal components like the grating, the plateholder, and the scanning exit slit are easily removable. The radius of curvature of the Rowland cylinder can also be easily changed. The entrance beam is always kept fixed in position and direction, allowing the instrument to be permanently aligned with fixed light sources. The vacuum case is mechanically independent from the optical components.     

Measurement of the Differential Ray Velocity and Longitudinal Magnetic Field on the Sun with CCD Photodetectors: Part I. Modulationless Method

A method for measuring the differential ray velocity and magnetic field strength on the sun in the modulationless mode with the use of a diffraction-grating spectrograph and CCD-based photodetectors is described. The optical arrangement of the device implementing this method is presented, and its operating principles are considered. The basic formulas for signal calculation are presented. The main advantages of this technique are the reduces effect of distorting atmospheric instabilities and suppression of the intrinsic noise of the grating spectrograph.     

基于单片机的光纤Bragg光栅传感器的解调系统

长期以来,对光纤Bragg光栅传感器反射波长的检测是采用光谱仪,随着光纤Bragg光栅传感器应用的不断发展,光谱仪表现出越来越多的局限性.本文利用调谐法布里-珀罗腔多光束传播,当法布里-珀罗腔满足特定条件时其透射光可达到最强或最弱原理,建立了F-P腔解调系统模型,通过检测F-P腔的相关参数而得到所测的参变量;根据光纤Bragg光栅自身特性,建立了匹配滤波法解调系统模型,应用另一光纤Bragg光栅跟踪被测光纤Bragg光栅的变化,从而得到所测量;论文指出了应用时在这两种解调方案中需要解决的关键问题.为了提高系统测量的准确性和实时性,系统采用单片机系统处理相关数据信息.本文系统详细阐述了在解调系统中单片机的应用及相关接口模型,给出了详细的软硬件设计.     

高分辨率阶梯光栅光谱仪的光学设计

简述阶梯光栅的基本原理和在天文学中的应用,分析并比较了阶梯光栅光谱仪与普通平面闪耀光栅光谱仪的区别。为正在研制中的一架国产4m通光口径的光谱巡天望远镜(简称LAMOST)设计了高分辨率阶梯光栅光谱仪的光学方案,该设计方案采用了白光孔径准直镜系统,大闪耀角的R4阶梯光栅和无遮拦的离轴折叠Schmidt照相机。