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1.
刘传胜  李林  曹银花  张颖 《光学技术》2004,30(3):270-272
由于变焦系统的凸轮曲线对变焦过程中像面的稳定、操作的灵活性都有重要影响,因此变焦曲线的优化设计有着重要的意义。首次采用遗传算法对机械补偿类型的变焦曲线进行了优化设计,并给出了实例。这样得到的曲线比传统的让变倍组作线性移动得到的曲线要明显平滑,证明了遗传算法用于变焦曲线优化设计的可行性和有效性。  相似文献   

2.
TH703 2004010033 用步进电机实现连续变焦距光学镜头的变焦控制=Realization of zooming control for a continuous zoom optical lenswith step motor[刊,中]/邹华(中科院光电技术研究所.四川,成都(610209)),张孟伟∥光电工程.—2003.30(1).—29-31,37 根据望远镜的工作原理,对变焦距光学镜头的变焦  相似文献   

3.
变焦系统凸轮曲线设计是变焦系统后期设计过程中十分重要的环节,曲线设计的好坏直接关系到系统像面的稳定程度.针对ZEMAX光学设计软件界面编写了三组元变焦系统凸轮曲线设计程序,确保像面稳定、像质优良.程序可准确给出凸轮曲线的数据和形状,借助该程序对变焦系统任意焦距位置的光学性能和像差特性进行实时评估,提高了变焦系统的设计效...  相似文献   

4.
变焦曲线拟合方法的比较与研究   总被引:1,自引:0,他引:1  
在机械补偿变焦距光学系统中,通过利用变焦曲线控制变倍组与补偿组的移动来达到变焦目的.因此,为使变焦距光学系统在变焦过程中能够始终成像清晰且稳定,拟合出良好的变焦曲线是十分必要的.本文运用动态光学理论、CODE V和ZEMAX宏三种方法分别对一个20倍变焦距光学系统进行变焦曲线拟合,得到相应的运动曲线方程.根据所得到的三组曲线方程,随机选取若干变焦位置点,分别对这些位置点的光学系统离焦量、中心视场MTF和边缘视场MTF进行评价.数据分析表明,动态光学理论拟合出的变焦曲线在满足系统要求前提下更能够保证像面的稳定性.  相似文献   

5.
常用的两运动组元等间距光学变焦驱动设计方法和等程距设计方法都存在曲线局部压力角难以控制的问题。论述一种基于基线交换的光学变焦驱动设计方法,该方法通过在合适的变焦曲线位置交换基线(主驱动曲线),从而解决曲线局部压力角(曲线在光轴方向切角的余角)控制的问题,保证了整个变焦过程中的主驱动曲线压力角一致性、扭矩力均匀性和变焦平滑性,同时不降低变焦过程的快速性。讨论了辅助程序设计的实现情况和实践中出现的问题的解决途径。理论和实践证明,这种变焦驱动设计方法是一种效果颇佳的设计优化手段。  相似文献   

6.
林忠  黄陈蓉  卢阿丽 《应用光学》2015,36(5):684-690
为了保持数字高清监控摄像机在大倍率电动变焦过程中的图像清晰度水平,提出一种新的电动变焦跟踪方法。该方法根据事先采集的若干条变焦曲线,利用几何法构造置信区间。以置信区间为变焦跟踪曲线的中心位置并且自适应地调整置信区间的位置,从而动态地修正变焦跟踪曲线。在18数字高清摄像机中实现了该方法,实验结果显示:变焦过程中对焦电机的调节位置相对于最佳位置的平均偏离水平不大于0.018 75 mm;变焦全程时间平均为4.1 s。  相似文献   

7.
PapersTheory of Nonlinear Interaction of Finite Amplitude Random Sound Waves—Du Gonghuan(杜功焕), Gong Xiufen(龚秀芬)and Zhu Zhemin(朱哲民),1(l982),No.1,1—8.Reflection and Refraction of Plane Sound Waves in Moving Stratified Media —Yang Xunren(杨训仁), 1(l982),No.l,9—22.Turning-Point Convergence-zones in Underwater Sound Channels(Ⅱ)A Generalized Ray Theory—Zhang Renhe(张仁和),1(l982),No.l,23—34.A New Method of Adaptive Array Processing for Signals of Unknown Characteristics—Hou Chaohuan (侯朝焕)and Yan Shizun(阎世尊),1(l982),No.l,35—47.Acoustical Method for Classification of Seafloor SeJiments—Meng Jinsheng(孟金生)and Guan Dinghua (关定华),1(l982),No.l,48—53.  相似文献   

8.
<正>Updated September 2013 by S.Hashimoto(KEK),J.Laiho(Syracuse University),and S.R.Sharpe(University of Washington).18.1.Lattice regularization of QCD Gauge theories form the building blocks of the Standard Model.While the SU(2)and U(l)parts have weak couplings and can be studied accurately with perturbative methods,the SU(3)component—QCD—is only amenable to a perturbative treatment at high energies.The growth of the coupling constant in the infrared—the flip-side of asymptotic freedom—requires the use of non-perturbative methods to determine the low energy properties of QCD.Lattice gauge theory,proposed by K.Wilson in 1974[1],provides such a method,for it gives a non-perturbative definition of vector-like gauge field theories like QCD.In lattice regularized QCD—commonly called lattice QCD or LQCD—Euclidean space-time is discretized,usually on a hypercubic  相似文献   

9.
The UV-Vis and infrared (IR) absorption spectra of organophosphorus (OP) pesticides have been studied. A correlation in spectra was developed to optimize the OP pesticides in the environments. The spectroscopic (UV-Vis and IR) spectrum of OP pesticides like methyl parathion, malathion and parathion has been interpreted in detail. A complete calculation of the normal frequencies and absolute intensities of UV-Vis and IR absorption bands are interpreted with the help of corresponding experimental data. In the colorimetric reactions, the bands appear at 2 077, 1 637, 1 455, 1 015, 655 cm-1 for malathion; 2 081, 1 639, 1 316, 1 015, 794, 683 cm-1 for parathion; 2 078, 1 632, 1 032, 794 cm-1 for methyl parathion were used for quantitative or qualitative analysis. All these IR spectra were acquired by averaging 100 scans at a resolution of 4 cm-1. It is determined experimentally in the region 200~450 nm for UV-Vis absorption bands and in the region 400~4 000 cm-1 for IR absorption bands. It is concluded that the mainly optically active groups (P—OH, CO, PO, C—O—C, P—O—C, PS, —OH) present in pesticides which are responsible in change in significant data for quantitative and qualitative analysis. The various optical properties like wavelength, band energy, wave number, and frequency, also are calculated.  相似文献   

10.
O7212006054609晶体吸收对X射线衍射峰形状的影响=Peak shape of X-ray diffraction effected by absorption of crystal[刊,中]/陈惠芬(上海应用技术学院材料系.上海(200233)),刘克家//常熟理工学院学报.—2006,20(2).—39-41,81考虑到不同深度的晶面对X射线的吸收的差别,得出了晶粒衍射线的峰形曲线,此峰形曲线近似平方反比曲线(I∝1/(Δθ)2)。图2(严寒)O7342006054610折射率正负交替的光子晶体的光学特性研究=Study ofoptical properties of a photonic crystal with NI M-PI Mal-ternant multilayer[刊,中]/王慧琴(南昌大学近代…  相似文献   

11.
变焦系统凸轮曲线的优化设计   总被引:4,自引:1,他引:3  
陈鑫  付跃刚 《应用光学》2008,29(1):45-47
由于变焦系统凸轮曲线的的质量直接影响像质,因此从实际应用出发,以变焦方程和动态光学原理为依据,结合实际工作中需要设计的变焦镜头,通过对变焦系统高斯计算的过程进行分析,指出影响凸轮曲线的主要因素为变倍组和补偿组的焦距以及二者的间隔。针对3个参量之间的对应关系进行讨论,提出了优化凸轮曲线的方法。  相似文献   

12.
ACOUSTICAL NEWS     
The conference,held in Gdansk—Jastrzebia Gora,Poland on 19—21 May 1987,wassponsored by the International Union of Pure and Applied Physic——Commission on Acoustics,the Polish Academy of Sciences——Committee on Acoustics,the Polish Acoustical Society,andthe Polish Noise Abatement League.The University of Gdansk and the Technical University ofGdansk supported the activities of the Organizing Committee.The International AdvisoryCommittee consisting of 49 outstanding acoustichas helped in the preparations for the conference.Most of the Advisory Committee members took part in the conference.  相似文献   

13.
为了使机械补偿的连续变焦光学系统可以连续、平稳地成像,提出了一种减小变焦系统凸轮曲线压力角的方法.改变变倍曲线方程,运用动态光学原理,拟合的补偿曲线的压力角有明显减小趋势.原始设计变倍曲线的压力角为31.4°,补偿曲线的最大压力角大于50°.运用插值法改变变倍组方程,得到的变倍曲线的最大压力角小于37°,补偿曲线的最大压力角小于23°,得到的新的凸轮曲线满足曲线压力角小于45°的要求.实际光学系统检测的结果证明了这种方法的可行性.该方法可以有效地减小凸轮曲线的压力角,实际变焦系统能够连续清晰地成像.  相似文献   

14.
The existence of strong interfercnce is the main constraint factor,which influences the detection performance of a signal extraction system.For asonar with large array the problem of anti-interferences in all-direction has not beensolved yet because of the requirements of over-long time delay line and the over highinput-output rate.A method proposed in this paper can be used in the design ofadaptive signal processing system with large array for suppressing the strong inter-ference in all-direction.This is a combined architecture of adaptive noise canceller(ANC)and a programmable DICANNE system.When the incident angle betweensignal θ_s and interfercnce θ_I is small,the ANC system is used.when θ_s—θ_I islarge,a programmable DICANNE system,with rising sampling rate,is used,so thatan all—directional anti—interfercnces system can be obtained.The structure des-cribed in this paper is easy to implement in hardware by using DSP chips.The designdiagram and implementable method in hardware is presented.  相似文献   

15.
通过对仅有单层介电薄膜双液体变焦透镜模型的相关理论分析,得出介电层薄膜的厚度及均匀性对双液体变焦透镜的性能影响很大,并绘制了双液体变焦透镜焦距与驱动电压、介电层厚度的关系曲线.在此基础上,以降低双液体变焦透镜的驱动电压为目的,对介电层的选择进行了分析,选择既可充当介电层又可充当疏水层的派瑞林材料作为双液体变焦透镜的介电层材料,通过真空蒸发镀膜工艺得到了合适厚度的介电层派瑞林薄膜,并对所镀薄膜表面形貌以及厚度进行了测试.选择氯化钾以及溴代十二烷作为导电液体和油性液体,利用离心方式除去液体中溶有的气体,进而制作完成双液体变焦透镜样品.电驱变焦实验得到低压双液体变焦透镜样品的变焦范围为±20mm,驱动电压约为30V,对于实验过程中出现的迟滞效应,通过对杨氏方程中引入摩擦力项,合理地解释了其原因.  相似文献   

16.
基于液体透镜的变焦系统不需要移动光组即能实现变倍的功能,这种变倍工作方式可应用于具有特定需求的成像系统,近年来备受关注。探讨了液体透镜参数(变焦范围,通光口径)对变焦系统变焦性能的影响,从理论上得到了液体透镜变焦系统最大变倍比以及最大视场角的计算公式。根据理论计算的结构,求得该结构下液体透镜变焦系统的变焦曲线表达式。从变焦曲线可知,系统从短焦向长焦方向变化时,系统变倍比增长速度越快,系统焦距变化越灵敏。利用上海理工大学研发的液体透镜进行仿真,设计了一款变倍比为6,全视场角为60°的液体透镜变焦系统高斯结构。该设计不仅验证了理论推导的正确性,也可作为实际液体透镜变焦系统的初始结构。  相似文献   

17.
Different mass percent polyacrylonitrile (PAN)—polyethylene oxide (PEO) gels were prepared and irradiated by an electron beam (EB) with energy of 1.0 MeV to the dose ranging from 13 kGy to 260 kGy. The gels were analysed by using Fourier transform infrared spectrum, gel fraction and ionic conductivity (IC) measurement. The results show that the gel is crosslinked by EB irradiation, the crosslinking degree rises with the increasing EB irradiation dose (ID) and the mass percents of both PAN and PEO contribute a lot to the crosslinking; in addition, EB irradiation can promote the IC of PAN—PEO gels. There exists an optimum irradiation dose, at which the IC can increase dramatically. The IC changes of the PAN—PEO gels along with ID are divided into three regions: IC rapidly increasing region, IC decreasing region and IC balanced region. The cause of the change can be ascribed to two aspects, gel capturing electron degree and crosslinking degree. By comparing the IC—ID curves of different mass percents of PAN and PEO in gel, we found that PAN plays a more important role for gel IC promotion than PEO, since addition of PAN in gel causes the IC—ID curve sharper, while addition of PEO in gel causes the curve milder.  相似文献   

18.
Physics design of CYCAIE-100   总被引:2,自引:0,他引:2  
The design and construction of Beijing Radioactive Ion-beam Facility (BRIF) was started at China Institute of Atomic Energy -CIAE) in 2004. In this project, a 100 MeV high intensity cyclotron, CYCIAE-100, is selected as a driving accelerator for radioactive ion beam production. It will provide a proton beam of 75—100 MeV with an intensity of 200—500 μA. The scheme adopted in this design, i.e.,  相似文献   

19.
塑料闪烁体中子探测效率及相对发光产额的标定   总被引:1,自引:0,他引:1  
利用加速器中子源研究了用于标定塑料闪烁体中子探测效率及相对发光产额的实验技术 ,在四川大学原子核科学技术研究所 2 .5MeV静电加速器上 ,利用T(p,n)和D(d ,n)核反应作为中子源 ,在 0 .6—5MeV中子能区对直径为 40mm ,厚度为 5mm的 1 42 1塑料闪烁体的中子探测效率及相对发光产额进行了测定.A method used for the calibration of neutron efficiency and the relative photo yield of plastic scintillator is studied. T(p,n) and D(d,n) reactions are used as neutron resources. The neutron efficiencies and the relative photo yields of plastic scintillators 1421 (40 mm in diameter and 5 mm in thickness) are determined in the neutron energy range of 0.655—5 MeV.  相似文献   

20.
Recent measurements of event-by-event elliptic flow in Au Au collisions at S_(NN)~(1/2)=200GeV exhibit large relative fluctuations of about 40%—50%.The data are well described by fluctuations in the shape of the initial collision region,as estimated event-by-event with the participant eccentricity using Glauber Monte Carlo.These results,combined with the demonstrated participant eccentricity scaling of the elliptic flow across nuclear species,constitute evidence of transverse granularity in the initial matter production in these collisions.  相似文献   

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