N—1型鼓轮式高速摄影机设计

N—1型鼓轮式高速摄影机是根据科学院力学所研制的脉冲He—Ne激光光源配套使用要求而设计的。摄影机采用鼓轮内表面装片形式,用35mm底片;鼓轮外径为500mm用等强度原理设计;鼓轮由电机直接带动,用光电测速,画幅尺寸为8×22mm~2时摄影频率可达4000幅/秒;摄影物镜与DF照相镜物镜通用,可换用f’=58mm,105mm,135mm;取景放大镜为5×;装卸底片用特殊设计的装片门及可拆卸暗袋。     

GS240/35高速电影摄影机抓片机构介绍与分析

GS240/35高速电影摄影机是一种间歇式高速电影摄影机,频率可达240幅/秒,使用35毫米胶片,画幅大小为22×18毫米。间歇运动的主要部件——抓片机构的结构和特性,直接影响摄影机的频率和画幅质量。     

XGS—12型高速电影摄影机

XGS-12型摄影机是西安光机所新近推出的又一种16mm棱镜补偿式高速电影摄影机,其画幅尺寸为7.5×10.4mm~2时的最高拍摄频率为11000fps。该机性能优异,附件齐全,本文对该机将从光学系统摄影机和电控制系统三个部分加以介绍。     

70mm间歇式同步高速摄影机系统的研究

70 mm同步高速摄影机系统主要是用于拍摄激光制导炸弹、火箭、导弹的三维飞行姿态和空间参数的测试设备,具有画幅大、速度高、机动灵活的特点.简要介绍了该摄影机系统的总体组成与各部分的工作原理,并着重描述了摄影机系统的设计及性能指标.鉴于该系统已成功应用,因而可为其他摄影机系统的设计提供一定参考.     

TGS—200/35型高速电影摄影机抓片爪加工工艺浅谈

TGS—200/35同步高速电影摄影机,是一种使用35毫米胶片的间歇抓片式高速电影摄影机,它的拍摄频率可达240帧/秒,同步拍摄频率最高200帧/秒。该机的间歇输片是靠双边六爪的抓片爪(见图)和双边四爪的定片针准确配合来实现的,而抓片爪设计与加工质量,是摄影机拍摄频率和画幅质量能否达到设计指标的关键因素。 TGS—200/35的抓片爪,几何形状复杂,尺寸精度和形位公差要求比较高。     

超高速摄影用高强度铝合金转镜动态特性的研究

转镜型超高速摄影机的信息容量取决于转镜的材料和横截面形状.本文首次对超高速摄影用高强度铝合金转镜从理论和实验两个方面进行了系统研究.研究表明:高强度铝合金是超高速分幅摄影机转镜的理想材料;当铝转镜截面形状为正三角形、镜面尺寸为(17×32.5)mm²时,转速已达(50×10⁴)rpm,镜面尺寸为(33×24)mm²时,转速已达(40×10⁴)rpm.     

70 mm高速摄影机抓片机构动平衡计算

对70 mm间歇式同步高速摄影机的曲柄摇杆式抓片机构动平衡计算方法、实施途径和结果进行了分析研究.利用MSC/Visual Nastran Desktop软件,在该抓片机构虚拟样机上进行了动平衡计算.计算结果为工程设计提供了可靠的设计数据和理论依据,改善了实际的动平衡质量,提高了摄影频率.应用实践证明,采用动力学仿真方法进行动平衡计算,可简化抓片机构动平衡的计算过程,并提高了计算准确度和设计效率.     

空间硬X射线编码孔成像望远镜样机的研制及初步实验结果

介绍了研制的一台空间硬X射线编码孔成像望远镜样机, 使用的位置灵敏探测器为CdZnTe半导体阵列探测器, 面积50mm×50mm, 位置分辨1.6mm. 码板材料为钨铁镍合金, 厚度0.7mm, 码元素尺寸3.2mm×3.2mm. 介绍了码板的编码技术、光学设计和图像重建方法. 实验室测定了样机的性能, 探测器对59.54keV(²⁴¹Am)的能量分辨率为11.6%. 成像实验对单个伽玛射线源的定位 精度为0.12°, 双源角分辨好于0.42°.     

虚拟制造技术在高速摄影机研制中的应用

结合70 mm间歇式同步高速摄影机的虚拟制造实例，阐述了虚拟制造技术在高速摄影机研制中的应用与具体实现，包括虚拟环境构造、数字化模型建立、装配性和适配性检查以及关重件的动力学仿真.事实证明，将虚拟制造技术应用于高速摄影机的研制不仅可以提高高速摄影机的设计质量，而且可以大大节约产品开发时间.     

网格高速摄影的理论与实践——BY-90型机研制和BY-92型机设计

我校在国内首创研制了BY—90型网格式高速摄影机,并已通过了技术签定。在此基础上,改进设计了BY—92型高速摄影机,其技术性能是:网格板微透镜间距0.4mm,焦距1.6mm,网格板面积100×125mm~2,像素数约80000个;摄影物镜焦距200mm,相对孔径1:2.77;摄影频率1000—15×10~4幅/秒可调;总画幅数达300幅,     

Surface potential decay of DC-corona-charged PET films on humid electrodes

Surface potential decay measurement is a widely used tool to test the electrical properties of insulation materials. The aim of the present paper is to evaluate the effect of a humid electrode on the surface potential decay process. The experiments are performed on 1-mm thick samples of PET films (50 mm × 50 mm) in ambient air (temperature: 25 °C–29 °C; relative humidity: 42%–48%). The samples are placed on a grounded humid electrode (aluminum plate covered by a humid textile: 52 mm × 52 mm), and are charged by exposing them for 10 s to the negative DC corona discharge generated by a high-voltage wire-type dual electrode.The results show that the humid electrode has a significant influence on the surface potential evolution during the first moments after corona charging. Bipolar charge injection is the main physical mechanism that explains this potential decay.     

Effect of Host Medium on the Fluorescence Emission Intensity of Rhodamine B in Liquid and Solid Phase

In this work, we study the effect of concentration, host medium, PH and phase states on the fluorescence emission from the laser dye Rhodamine B pumped by UV laser as exited source. The polymethylmethacrylate PMMA is used as a host medium in case of solid phase samples while, ethanol and Tetrahydrofuran (THF) are used in case of a liquid one. Laser Induced Fluorescence (LIF) technique was used to study the fluorescence properties of both cases of liquid and thin film solid-state samples. In addition, the Dual Thermal Lens (DTL) technique was used to study the quantum yield of these samples. The concentrations of Rhodamine B in ethanol as solvent between 2 × 10⁻² M and 5 × 10⁻⁶ M were studied. The maximum fluorescence emission is observed at concentration of Rhodamine B C = 3 × 10⁻⁴ M. Comparison studies were investigated for different host medium such as ethanol, THF, PMMA in liquid phase state and PMMA in solid phase state. The measurements revealed that, the behavior of both phases state was analogous. Rhodamine B/PMMA thin film sample by ratio of 4:1 and thickness 0.12 mm was found to have the best photostability sample with a quantum yield about ≈0.82.     

基于蛇形光路的PET探测器作用深度提取方法

为实现正电子发射断层成像(Positron Emission Tomography,PET)探测器的作用深度(Depth Of Interaction,DOI)信息获取,本文提出一种基于分光技术的探测器设计方案.探测器采用晶体单元与硅光电倍增管(Silicon Photomultiplier,SiPM)一对一耦合、蛇形光路的设计和单端Anger加权读出方法进行DOI解码.基于GATE软件进行蒙特卡罗模拟,建立8×1的LSO晶体阵列(单根晶体尺寸3.1×3.1×20mm3);模拟泛场照射获取位置查找表;并进行不同深度的模拟,获得各晶体在各深度的空间分辨率.结果显示所模拟的探测器模块DOI分辨率在1.0~6.7mm之间,平均值为3.2mm.本文提出的基于蛇形光路的PET探测器方案能在维持系统成本和复杂度的前提下实现DOI解码,提升PET系统的成像性能.     

Large composite infrared high-vacuum windows made of NaCl

We describe the fabrication of large NaCl vacuum windows (384 × 70 × 30 mm) made by cementing together two halves of 192 mm length. These windows have been used successfully for more than 2 years on the TCA tokamak to provide diagnostic access.     

Computer-generated holograms using (Se,S)-based chalcogenide amorphous film

New computer-generated holograms using As-Se-S-Ge chalcogenide amorphous film are presented. The chalcogenide film is sensitive to an electron beam and has a high resolution (3000 lines/mm). Utilizing a fine focused electron beam and a high resolution of the amorphous film, full size computer-generated holograms can be directly fabricated without reducing process, and thus a real-time process is possible. Computer-generated holograms with 64 × 64 cells have been experimentally demonstrated in 560 μm × 560 μm hologram size.     

流延法制备高锂离子电导Li_(1.4)Al_(0.4)Ti_(1.6)(PO_4)_3固态电解质及其环氧树脂改性

以溶胶凝胶法合成的高纯Li_(1.4)Al_(0.4)Ti_(1.6)(PO_4)_3(LATP)纳米晶体粉末为原料,通过流延法成膜,在950℃下煅烧5 h合成LATP固态电解质片;对其进行环氧树脂改性后,能量色散X射线光谱元素图像表明环氧树脂完全浸入LATP内部,可以有效防止水渗透.研究发现流延法合成的LATP固态电解质在25℃?C时电导率高达8.70×10~(-4)S·cm~(-1)、活化能为0.36 eV、相对密度为89.5%.经过环氧树脂改性后电导率仍高达3.35×10-4S·cm-1、活化能为0.34 e V、相对密度为93.0%.高电导隔水的环氧树脂改性LATP固态电解质可作为锂金属保护薄膜用于新型高比容量电池.     

Factors that influence the surface potential decay on a thin film of polyethylene terephthalate (PET)

The initial potential at the surface of the sample, as well as the temperature and the relative humidity of the ambient air are known to influence the surface-potential decay characteristics of corona-charged thin insulating films. The aim of the present work is to demonstrate the effectiveness of the Experimental Design methodology for evaluating the effects of these factors. Thus, a full factorial experimental design was carried out on a thin film of polyethylene terephthalate (thickness: 0.5 mm; surface: 50 mm × 50 mm). A negative corona discharge produced in a needle–grid–plate electrode system was employed to charge the surface of the film samples. The variation domains for the three factors were respectively: ?1000 V to ?1800 V; 25 to 55 °C; 50% to 80%. The surface-potential decay process was characterized by two output variables: the time needed for the potential to reduce to respectively 50% and 10% of the initial value. It was found that the former is more affected by the temperature, while the latter is more sensitive to the variation of the relative humidity.     

Aberration-corrected catadioptric magnifiers useful for simple microfiche readers

The present paper considers the magnifying power and aberration properties of three different catadioptric magnifying systems useful for application as simple hand-held microfiche readers. These are in the form of a plano-convex lens, a meniscus lens and an achromatic doublet lens and all their outer surfaces have been coated with a semi-reflecting film so that they behave like catadioptric elements. These can be designed to give magnification in the range of 15 × to 25 × with sufficient eye relief. Using such magnifiers, it is possible to read microfiche having frame sizes of 16 × 12 mm and 12 × 9 mm. The cemented achromatic doublet coated on the outer surfaces seems to give a very good image for use in microfiche reader.