检索结果-内蒙古大学图书馆

Stepwise angular spectrum method for curved surface diffraction

OPTICS EXPRESS 2014年第10期22卷 12659-12667页

作者： Hwang, Chi-Young Oh, Seungtaik Jeong, Il-Kwon Kim, Hwi Elect & Telecommun Res Inst Taejon 305700 South Korea Korea Univ Coll Sci & Technol Elect & Informat Engn Dept Sejoing 339700 South Korea

We present a method to calculate wave propagation between arbitrary curved surfaces using a staircase approximation approach. The entire curved surface is divided into multiple subregions and each curved subregion is approximated by a piecewise flat subplane allowing the application of conventional diffraction theory. In addition, in order to reflect the local curvature of each subregion, we apply the phase compensation technique. Analytical expressions are derived based on the angular spectrum method and numerical studies are conducted to validate our method. (C) 2014 Optical Society of America

关键词： computation methods Diffraction theory Digital holographic imaging Fresnel diffraction Phase compensation Wave propagation

来源：评论

学校读者我要写书评

暂无评论

Allowing for roughness when calculating the reflection of optical radiation in a three-dimensional object

引用

JOURNAL OF OPTICAL TECHNOLOGY 2014年第2期81卷 56-60页

作者： Klass, E. V. Shakhovskii, V. V. Badyuk, K. V. Ul'yanov, S. A. Cent Sci Res Inst Chem & Mech Moscow Russia

This paper describes a technique for calculating the reflection of optical radiation from a rough three-dimensional object in the approximation of geometrical optics, using the Monte Carlo method. To allow for roughness, along with a macroscopic model of the object, a model is introduced at the microlevel, consisting of a substrate of finite size on which inhomogeneities are specified in the form of bodies bounded by second-order surfaces. The influence of edge effects on the microlevel model is investigated, and its optimal dimensions are selected. Results of the testing of the technique are presented, using experiments to determine the reflective properties of materials with a known degree of random roughness and of a three-dimensional object in the form of a biconical radiator. (C) 2014 Optical Society of America.

关键词： computation methods Geometric optics Multiple scattering Reflection Rough surface scattering Roughness

来源：评论

学校读者我要写书评

暂无评论

High-level interface to T-matrix scattering calculations: architecture, capabilities and limitations

引用

OPTICS EXPRESS 2014年第2期22卷 1655-1660页

作者： Leinonen, Jussi Finnish Meteorol Inst FI-00101 Helsinki Finland

The PyTMatrix package was designed with the objective of providing a simple, extensible interface to T-Matrix electromagnetic scattering calculations performed using an extensively validated numerical core. The interface, implemented in the Python programming language, facilitates automation of the calculations and further analysis of the results through direct integration of both the inputs and the outputs of the calculations to numerical analysis software. This article describes the architecture and design of the package, illustrating how the concepts in the physics of electromagnetic scattering are mapped into data and code models in the computer software. The resulting capabilities and their consequences for the usability and performance of the package are explored. (C) 2014 Optical Society of America

关键词： Atmospheric optics computation methods Electromagnetic scattering Numerical analysis Particle scattering Remote sensing

来源：评论

学校读者我要写书评

暂无评论

Mode solver based on Gegenbauer polynomial expansion for cylindrical structures with arbitrary cross sections

引用

JOURNAL OF THE OPTICAL SOCIETY OF AMERICA A-OPTICS IMAGE SCIENCE AND VISION 2014年第4期31卷 667-676页

作者： Edee, Kofi Abboud, Mira Granet, Gerard Cornet, Jean Francois Gippius, Nikolay A. Univ Blaise Pascal Clermont Univ Inst Pascal F-63000 Clermont Ferrand France CNRS UMR 6602 Lasmea F-63177 Aubiere France

We present a modal method for the computation of eigenmodes of cylindrical structures with arbitrary cross sections. These modes are found as eigenvectors of a matrix eigenvalue equation that is obtained by introducing a new coordinate system that takes into account the profile of the cross section. We show that the use of Hertz potentials is suitable for the derivation of this eigenvalue equation and that the modal method based on Gegenbauer expansion (MMGE) is an efficient tool for the numerical solution of this equation. Results are successfully compared for both perfectly conducting and dielectric structures. A complex coordinate version of the MMGE is introduced to solve the dielectric case. (C) 2014 Optical Society of America

关键词： computation methods Diffraction gratings Finite element method Scattering Waveguide cores Waveguides

来源：评论

学校读者我要写书评

暂无评论

Initial design with L² Monge-Kantorovich theory for the Monge-Ampere equation method of freeform optics

Initial design with L<SUP>2</SUP> Monge-Kantorovich theory f...

引用

International Optical Design Conference (IODC)

作者： Wu, Rengmao Zhang, Yaqin Benitez, Pablo Minano, Juan C. Univ Politecn Madrid Cedint Campus Montegancedo Madrid 28223 Spain Zhejiang Univ State Key Lab modern Optic Instrumentat Hangzhou 310027 Zhejiang Peoples R China

ISBN: (纸本)9781628413786

The Monge-Ampere (MA) equation arising in illumination design is highly nonlinear so that the convergence of the MA method is strongly determined by the initial design. We address the initial design of the MA method in this paper with the L-2 Monge-Kantorovich (LMK) theory, and introduce an efficient approach for finding the optimal mapping of the LMK problem. Three examples, including the beam shaping of collimated beam and point light source, are given to illustrate the potential benefits of the LMK theory in the initial design. The results show the MA method converges more stably and faster with the application of the LMK theory in the initial design.

关键词： Illumination design nonimaging optics freeform surface computation methods

来源：评论

学校读者我要写书评

暂无评论

Fat rays revisited: a synthesis of Physical and Geometrical Optics with Gauβlets

Fat rays revisited: a synthesis of Physical and Geometrical ...

引用

International Optical Design Conference (IODC)

作者： Greynolds, Alan W. 10741 E Placita Metate Tucson AZ 85749 USA

Decomposed into Gau beta lets (Gaussian beamlets or "fat rays"), a diffracting wavefield can be propagated through an optical system by simple ray tracing. As an update to a 1990 ILDC presentation, the metho... 详细信息

ISBN: (纸本)9781628413786

关键词： Propagation methods diffraction theory wave propagation computation methods

来源：评论

学校读者我要写书评

暂无评论

The lipophilicity indices of flavonoids estimated by reversed-phase liquid chromatography using different computation methods

引用

JOURNAL OF SEPARATION SCIENCE 2009年第12期32卷 2066-2074页

作者： Briciu, Rodica Domnica Kot-Wasik, Agata Namiesnik, Jacek Sarbu, Costel Univ Babes Bolyai Fac Chem & Chem Engn RO-400028 Cluj Napoca Romania Gdansk Univ Technol Fac Chem Gdansk Poland

The chromatographic behavior of some flavonoids was established by RP-HPLC on RP-18 (LiChroCART, LiChrosphere RP-18e), RP-8 (Zorbax, Eclipse XDB-C8), CN (Saulen-technik, LiChrosphere CN100) columns. The mobile phases were mixtures of methanol-water in different volume proportions from 70 to 80% v/v for RP-18 and RP-8, while for the CN column the proportions were between 66 and 70% v/v. The lipophilicity was expressed through different lipophilicity descriptors such as mean of k (mk), mean of log k (mlog k), log k(w), S, f(0), and scores of k and log k corresponding to the first principal component. The experimental lipophilicity indices are directly correlated with the computed values, via computer software and internet module, at a high analytical level. Furthermore, the results obtained applying principal component analysis to k and/or log k values allow the prediction and explanation of the interaction involved in the retention mechanism which takes place between the compounds and the employed stationary phases during the development.

关键词： computation methods Flavonoids Lipophilicity Principal component analyis RP-HPLC

来源：评论

学校读者我要写书评

暂无评论

Compressive direct measurement of the transverse photonic wavefunction

Compressive direct measurement of the transverse photonic wa...

引用

Frontiers in Optics

作者： Mirhosseini, Mohammad Magaña-Loaiza, Omar S. Hashemi Rafsanjani, S.M. Boyd, Robert W. The Institute of Optics University of Rochester RochesterNY14627 United States Center for Coherence and Quantum Optics Department of Physics and Astronomy University of Rochester RochesterNY14627 United States Department of Physics University of Ottawa OttawaONK1N 6N5 Canada

We generalize the method of direct measurement and combine it with compressive sensing. Using our method, we measure a 19200-dimensional state using only 20% of the total required measurements. © 2014 Optical Soc... 详细信息

ISBN: (纸本)1557522863

关键词： computation methods Fourier transforms Photon polarization Single mode fibers Single mode lasers Spatial light modulators Phase retrieval (100.5070) Quantum optics (270.0270) Quantum information and processing (270.5585)

来源：评论

学校读者我要写书评

暂无评论

Fully analytical evaluation of optical gain coefficient in bulk semiconductors in quasi-equilibrium free-carrier approximation

引用

Chinese Optics Letters 2014年第8期12卷 52-54页

作者： B.A.Mamedov Department of Physics Faculty of Arts and SciencesGaziosmanpas University

In this letter, a new analytical method is presented to calculate of the semiconductor optical gain coefficient. This method is particularly suitable for theoretical analyses to determine the dependence of semiconductor gain on the total carrier density and temperature in the semiconductor lasers. Also, the optical gain functions for semiconductor optical gain coefficient are presented analytically. The analytical evaluation is verified with numerical methods, which illustrates the accuracy of these obtained analytical expressions.

关键词： 140.0140 Lasers and laser optics 140.3380 Laser materials 140.5960 Semiconductor lasers 080.1753 computation methods

来源：评论

学校读者我要写书评

暂无评论

Investigation of a slope-point-based method for the design of aspheric surfaces in a catadioptric collimating optical system for a light-emitting diode source

引用

APPLIED OPTICS 2014年第29期53卷 H129-H139页

作者： Chen, Rung-Sheng Asia Univ Dept Photon & Commun Engn Taichung 41354 Taiwan

The aim of this paper is to develop a straightforward rigorous and flexible computational method to determine the coordinate points on an aspheric surface. The computational method chosen is based on the basic slope-point form of a straight-line equation [slope-point method (SPM)]. The practical instrumental example chosen to illustrate this method is a rotationally symmetric catadioptric collimator for a light-emitting diode (LED) source. This optical system has both a refractive and a totally internally reflective aspheric surface. It is a particularly illuminating example because it requires careful computational attention to the smooth transition between the refracting inner zones and the reflective outer zones of the aperture. The chosen SPM computational method deals satisfactorily with the transition points at the junction between the refractive and total internal reflecting (TIR) zones of the collimator. As part of this study, the effect of the position of the start point of the SPM surface evolution for the TIR zones of the collimator emerges as being particularly important, and the details of this are discussed. Finally, an extension of the basic SPM-based method is used to generalize the development of the catadioptric collimator surfaces to illustrate this general algorithm for aspheric surface design for an extended LED light source. (C) 2014 Optical Society of America

关键词： Collimation computation methods Freeform surfaces LED sources Refractive index Total internal reflection

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：