查询词典 Fresnel diffraction

X-ray diffraction is one of the most common and efficient ways to measure a superlattice structure. This dissertation displays the detail results for characterization of Ge〓Si〓/Si superlattices by x-ray diffraction (including x-ray small angle diffraction and double crystal diffraction). It was found, when the growth temperature is lower, the intensities of xray small angle diffraction peaks are modulated by a periodical function, which indicates that both sets of interfaces of the superlattice is highly flat; when the growth temperature is higher, the diffraction peak intensities are simply decay with the increase of diffraction vector, which indicates that one set of interfaces is highly flat but another is not; when the growth temperature is very high, the diffraction peaks are reduced more rapidly, which indicates that both sets of interfaces are not ideal.

本文详细介绍了用X-射线衍射（包括X-射线小角衍射和双晶衍射）方法对Ge〓Si〓/Si超晶格结构特性测试的结果，尤其是发现，当Ge〓Si〓/Si超晶格的生长温度较低时，X-射线小角衍射谱峰的强度随着衍射波矢的增加而周期性调制，表明超晶格的两套界面都十分平整；当生长温度较高时，Ge〓Si〓Si超晶格的X-射线小角衍射谱峰的强度随着衍射波矢呈简单的衰减变化，对应于超晶格内有一套界面不平整的情况；当生长温度进一步提高时，X-射线小角衍射峰明显减少，表明超晶格内两套界面都不理想。

In the paper, on the basis of aggregation of previous studies, the development of optical technology and development trends at home and abroad are introduced, the principle of Fresnel lens is summarized. In accordance with its principle, circle equidistant steps Fresnel lens design is described. And on this basis, based on Fresnel design, also based on a continuous upward spiral of the plane curve concept, incidence surface and the backlight is set up to greet Archimedes - Fresnel lens design formula and the Second parabolic type Fresnel lens design formula, and on this basis, the advantages and disadvantages of the three designs is discussed.

本文在充分了解非球面光学技术在国内外的发展状况和趋势的基础上，同时从菲涅尔透镜的光学原理出发，并根据它的工作原理推导了圆环等距菲涅尔透镜的设计步骤，并在此基础上依据菲涅尔的设计思想，同时依据平面曲线的连续又呈螺旋的构思，推导出了迎光面和背光面阿基米德型菲涅尔透镜的设计公式和二次抛物面型菲涅尔透镜的设计公式，并在此基础上讨论了这三种设计各自的优缺点。

In this thesis, several basic principles and phenomena of the Wave Optics are first intruducted briefly, they include the Huygens—Fresnel principle, diffraction of light ,Fresnel diffraction and Fraunhofer diffraction etc.

本文首先简要的介绍了衍射光学元件所涉及的波动光学中的几个基本原理和现象：惠更斯—菲涅耳原理、光的衍射、菲涅耳衍射和夫琅禾费衍射等。

The camera length of electron diffraction in transmisson electron microscopy is one of the main technical parameters in designing electron microscope and the electron diffraction analysis to microcrystal sample. According to Bragg law, the formula of calculating TEM electron diffraction camera length is derived from the research on the ray path of electron diffraction images in TEM and the comparison on electron diffraction with ordinary electronic diffractometer. The difference of physical significance of electron diffraction camera length between TEM and ordinary electronic diffractometer is discussed.

透射式电子显微镜(Transmisson Electron Microcopy， TEM)中的电子衍射相机长度，是电子显微镜设计和对微晶体样品进行电子衍射分析的主要技术参数之一依据布拉格定律，经对TEM中电子衍射成像光路的探讨与研究，并通过TEM与普通电子衍射仪的电子衍射的对比分析，导出了TEM电子衍射相机长度的精确计算公式，阐述了TEM和普通电子衍射仪的电子衍射相机长度所表征的物理意义的区别。

The diffraction theory of Kirchhoff is applied to the four-pinhole aperture diffraction screens, the intensity, the zero-contour of the real and imaginary parts of complex amplitude and the phase distribution in deep Fresnel diffraction region are simulated, and it is found that the bright spots in interference field show central symmetry distribution. When the observation plane close to the diffraction screen, the zero-value points of light intensity can form line segment, on which the eccentricities of the light intensity isoline are close or equal to 1, the intensity changes very fast on both sides of the zero-line of light intensity.

利用基尔霍夫衍射理论计算了四圆孔径衍射屏在菲涅尔深区形成的的干涉光场的强度、零值线和相位的分布，发现干涉光场亮斑关于中心呈对称分布，在距离衍射屏较近的观察面上，光强值为的零点组成光强零值线段，该线段上光强等值线的离心率都接近或等于1，其两侧的光强值变化非常剧烈。

As well known, modern laser diffraction has widely used in engineering measurement but it mostly limited in Fraunhofer diffraction because there is simple function between the size to be measured and space of diffraction dark spots and there are no analytic algorithm for Fresnel diffraction.

现代激光技术提供了极为良好的相干光源，该光源在工程测量，特别是衍射测量中得到广泛应用。但在实际应用中，往往局限于夫琅和费衍射，因为夫琅和费衍射法暗斑间距与被测尺寸之间具有很简单的函数关系S-n/d，而菲涅尔衍射光强分布非常复杂，缺乏解析的计算方法。

Staring from Fresnel diffraction integral,we deduced the optical intensity distribution in the Fresnel zone of the diffraction field of the annular-aperture lens axicon.

从菲涅耳衍射积分公式出发，推导多色高斯光束被球差透镜衍射后光强分布的解析公式，进行数值模拟和物理分析。

Based on the theory of fractional Fourier transform and one of its very important parameter, fractional order, the relationship between FRT and Fresnel diffraction are deduced and analyzed. The fractional Fourier transform hologram reconstructed with the Lohmann Ⅰ FRT system is presented and its computer simulation and digital reconstruction are realized. It is shown that FRT is an ideal tool to describe Fresnel diffraction,and the FRTH can record information on the object and the system at the same time,which extends the application areas of FRT and holography.

基于分数傅里叶变换理论并以分数阶这一重要参量为纽带，推导和分析了分数傅里叶变换与菲涅耳衍射之间的关系；提出了基于罗曼I型分数傅里叶变换系统的分数傅里叶变换全息图，并实现了其计算机生成及数字重现；研究表明，分数傅里叶变换是描述菲涅耳衍射的理想工具，分数傅里叶变换全息图可以同时记录物体和系统的信息，开拓了分数傅里叶变换和全息术的应用领域。

A method of the optical image encryption based on the frequency splitting domain and Fresnel domain is proposed, after the analysis of the fractional Fourier transform and Fresnel transform, by synthesizing the advantages of multi keys and lensless feature of the fractional Fourier transform and Fresnel transform in the optical image encryption system.

结合分数傅里叶变换及菲涅耳变换，在光学图像加密系统中分别具有多密钥性和无透镜性的优点，提出了基于分频域和菲涅耳域的光学图像加密方法。

The physical significance and the logical relation of the Fresnel diffraction and the Fraunhofer diffraction,along with the influence of inclination factor on diffraction pattern are discussed in detail.

导出了描述夫琅和费衍射的正确公式，讨论了菲涅耳衍射和夫琅和费衍射的物理意义、两者间的逻辑关系，以及倾斜因子k对衍射花样的影响。

The production moved off-Broadway to New York City, where she won the Joseph E. Calloway award for her performance, and was profiled in American Theater Magazine as one of ten young theater artists to watch.

生产提出过百老汇的新的纽约市，在那里她赢得了约瑟夫calloway奖，她的表现，并于异型在美国的战区杂志之一， 10战区的青年艺术家观赏。

It's a risk tradeoff, and I believe that adding test support code usually wins.

这是一个风险的权衡，我相信添加测试代码通常会占上风。