共查询到19条相似文献,搜索用时 109 毫秒
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采用一次性全息曝光的方法同时在样品上制备了周期分别为1μm和4μm,衍射效率电场可调的双重复合式液晶/聚合物光栅.使用He-Ne激光器对复合光栅的衍射特性进行了实验研究,发现光栅存在两个1级衍射极强峰.对峰值衍射效率的测定结果表明,周期1μm的光栅衍射效率为90%,周期4μm的光栅,60%.结合耦合波理论计算了周期1μm和4μm光栅的衍射效率理论值,分别为92.57%和63.68%.实验结果与理论值符合得非常好.对电光特性的测试表明该复合光栅内的两套子光栅的驱动电压V90关键词:
光栅
液晶 相似文献
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对称面形光栅TE模的衍射特性 总被引:3,自引:1,他引:2
本文采用耦合波方法计算了对称面形光栅的衍射效率,分析了光栅截面面形为正弦、三角形、矩形、梯形光栅衍射效率与光栅周期、沟槽深度的关系,计算了光栅的峰值衍射效率。理论计算表明:合理地选择光栅周期、沟槽深度,对称面形光栅都可以达到很高衍射效率,接近100%;光栅的峰值衍射效率基本出现在Bragg衍射且光栅的周期等于衍射波长时。 相似文献
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高密度光栅具有与传统光栅不同的性质,其衍射特性往往是偏振相关的。本文针对1550nm波长TE/TM偏振入射光和0.5的光栅占空比,利用严格耦合波分析数值计算了不同光栅周期下0级及-1级的衍射效率。研究表明,相比周期为1550nm的光栅,当周期为1200nm时,偏振相关衍射效应明显增强,当光栅周期为890nm时,TE偏振光的衍射效率随着光栅深度呈正余弦变化,而TM偏振光的衍射效率始终集中在0级,具有偏振选择性。通过模式方法,利用模式中的有效折射率概念,研究了不同周期下被入射光所激发的两种光波模式通过光栅区域传播所累积的相位差;基于双光束干涉,模拟了0级和-1级的衍射效率。结果表明,利用严格耦合波分析的数值计算结果符合模式方法的理论预期,对于高密度相位光栅的偏振选择性给予了合理的物理机制解释。 相似文献
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A. N. Artemiev A. D. Belyaev N. A. Artemiev A. A. Demkiv A. G. Maevsky O. Yu. Gorobtsov B. F. Kirillov G. A. Knyazev S. I. Tyutyunnikov V. N. Shalyapin 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2014,8(2):374-379
Equipment is constructed, a technique is developed, and experimental results on Debye-Scherrer diffraction in the backscattering geometry are obtained. A special program for diffraction ring processing is developed. The prospects for use of this technique for materials science purposes are discussed. 相似文献
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用计算机研究光的多缝衍射 总被引:5,自引:0,他引:5
依据光栅衍射理论,利用计算机的计算功能和作图功能对光的多缝衍射实验进行了模拟.由于采用了面向对象的编程语言C++,使得软件的使用非常简单,只要任意设定实验的参数,计算机就会快速地绘出各种复杂的衍射图线,并准确地再现光栅衍射的现象及规律.便于对光的干涉和衍射现象进行深入的研究。 相似文献
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In this paper, we describe a new computer simulation technique of generating Fresnel diffraction images from rectangular apertures of arbitrary dimensions by using Fresnel integrals instead of the more common fast Fourier transform methods. The simulation can be performed in almost any PC using the software MATLAB. Diffraction images can be generated for any wavelength of light and for any aperture–screen and aperture-source distances. Images for rectangular obstacles can also be simulated. Details of the algorithm and program are presented, as well as the interesting insights than can be gained from using the program. Finally, it is shown that the simulated images reduce to the simple Fraunhofer diffraction patterns for certain limiting situations. 相似文献
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Two advanced optical system applications are implemented in a Matlab™ based simulation engine. The applications are aligning a micro-optic fiber coupler and scanning an optical disk with a readout system having an effective numerical aperture of 1.8. Many phenomena, like scalar diffraction, vector diffraction, addition of aberrations, thin-film interactions, and Babinet decomposition are described in the examples. A powerful graphical user interface (GUI) is also described that allows users to define optical elements, program operations and control program flow. Users can also easily interface custom field operations to the simulation engine. 相似文献
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一种用于自动分析散斑摄影条纹图的数字图像复原技术——衍射晕影响的消除 总被引:2,自引:2,他引:0
本文提出了一种消除衍射晕非均匀照度影响、提高计算机自动测量散斑摄影条纹图精度的数字图像复原算法.简单介绍了散斑摄影条纹的自动分析过程.在VAX-11/785计算机上对模拟的无噪声白光散斑条纹进行验证,结果表明,本算法和程序是可靠的. 相似文献
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F. Jona D.W. Jepsen P.M. Marcus I.J. Rosenberg A.H. Weiss K.F. Canter 《Solid State Communications》1980,36(11):957-959
Four experimental spectra measured in a low-energy positron diffraction (LEPD) experiment on Cu{111} are satisfactorily matched by intensity calculations. The calculations were carried out with a computer program developed for LEED (low-energy electron diffraction) but using a potential consisting of negative Coulomb contribution, no exchange term and the correlation correction used normally for electrons. The present experimental data are not refined enough to show that positrons do not feel an exchange potential. 相似文献