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A high-order integral solver for scalar problems of diffraction by screens and apertures in three-dimensional space

Oscar P. Bruno, Stéphane K. Lintner
2013 Journal of Computational Physics  
We present a novel methodology for the numerical solution of problems of diffraction by infinitely thin screens in three dimensional space.  ...  We demonstrate our methodology with a variety of numerical results for screen and aperture problems at high frequencies---including simulation of classical experiments such as the diffraction by a circular  ...  The authors gratefully acknowledge support from AFOSR, NSF, JPL and the Betty and Gordon Moore Foundation.  ... 
doi:10.1016/j.jcp.2013.06.022 fatcat:3ixibp4kmbgkvligp3yx25baa4

Advances in hybrid finite element – boundary integral – multilevel fast multipole – uniform geometrical theory of diffraction method

A. Tzoulis, T. F. Eibert
2007 Advances in Radio Science  
The diffraction points on each pair of edges are determined by an iterative three-dimensional parametric realization of the generalized Fermat's principle.  ...  </strong> Numerical modeling of problems including composite metallic/dielectric objects with arbitrary shapes and electrically large conducting objects within a common environment is performed in an optimum  ...  The second example is a dielectric rod antenna in front of a large metallic screen with a quadratic aperture as depicted in Fig. 5 .  ... 
doi:10.5194/ars-5-101-2007 fatcat:67fagoxbcvempplam6pnwheuzi

Numerical Modeling of Millimeter-Wave Transmission Lines

Georg Michel
2010 IEEE Transactions on Plasma Science  
Quasi-optical and waveguide techniques are at hand for the design of transmission lines which in most cases are a combination of both approaches.  ...  The transmission of high-power millimeter waves for electron cyclotron resonace heating of plasmas is a well developed field which has reached a mature level over the years [1] .  ...  We can reduce the problem to the solution of the scalar wave equation by using the ansatz F(x, y, 0) = u(x, y)F 0 where u is a scalar function of the aperture coordinates, and F 0 is a constant three-dimensional  ... 
doi:10.1109/tps.2009.2039358 fatcat:d3q33qqh2zanhd7epotbrdcqv4

System simulation of a GLV projection system

Timothy P. Kurzweg, Jose A. Martinez, Steven P. Levitan, Abhijit J. Davare, Mark Kahrs, Donald M. Chiarulli, Hakan Urey
2003 MOEMS Display and Imaging Systems  
In this paper, we present a system-level simulation and analysis of a diffractive optical MEM Grating Light Valve.  ...  In this paper, we provide a brief background of the models that are used for signal and device simulation, and use these results for the simulation and analysis of the promising GLV device for applications  ...  The analysis is reduced to a two-dimensional problem in the plane of the displacement.  ... 
doi:10.1117/12.472861 fatcat:6cakrgyh6jbdvo3kyut4jhj7lu

Programmable lithography engine (ProLE) grid-type supercomputer and its applications

John S. Petersen, Mark J. Maslow, David J. Gerold, Robert T. Greenway, Anthony Yen
2003 Optical Microlithography XVI  
Our solution is to create a workbench that has a set of advanced user applications that utilize best-in-class simulator engines for solving litho-related DFM problems using distributive computing.  ...  of applications including advanced aberrations for lens sensitivity and flare studies, opticalproximity-correction for a bitcell and an application that will allow evaluation of the potential of a design  ...  The full scalar model is the same but adds the angular affect of the higher diffraction orders, not only the zero-diffraction-order.  ... 
doi:10.1117/12.485506 fatcat:oy7e7zrkzfh7jbp3zajfi6udbi

Method of Lines Transpose: A Fast Implicit Wave Propagator [article]

Matthew F. Causley, Andrew J. Christlieb, Yaman Guclu, Eric Wolf
2013 arXiv   pre-print
Our solver is built upon line objects and, combined with the flexibility of the integral solver, allows us to solve problems on arbitrary spatial domains, by embedding the boundary in a regular Cartesian  ...  We also demonstrate that the resulting solver remains fast even in the case of unstructured meshes, can incorporate domain decomposition, and allows for the implementation of Dirichlet, Neumann, periodic  ...  An idealized slit diffraction grating consists of a reflecting screen of vanishing thickness, with open slits of aperture width a, spaced distance d apart, measured from the end of one slit to the beginning  ... 
arXiv:1306.6902v1 fatcat:tbtkbwlwtbfoncmoa3x4bmrvsm

A Generalized Coupled Wave Theory of Volume Diffraction in Two Dimensions

J. W. Lewis, L. Solymar
1985 Proceedings of the Royal Society A  
A coupled wave theory of scalar volume diffraction by two-dimensional transmission gratings is form ulated in term s of the Fourier spectrum.  ...  This would allow the treatm ent of polarization and three-dimensional problems.  ...  Conservation of power by the DIFFRACTED SPECTRUM The exact solution of the wave equation (1) would involve fields propagating and evanescent in both positive and negative x directions in the homogeneous  ... 
doi:10.1098/rspa.1985.0025 fatcat:gkzzdbpoljd27gz3td65fkzyw4

A frequency-independent boundary element method for scattering by two-dimensional screens and apertures [article]

David P. Hewett and Stephen Langdon and Simon N. Chandler-Wilde
2014 arXiv   pre-print
We propose and analyse a hybrid numerical-asymptotic hp boundary element method for time-harmonic scattering of an incident plane wave by an arbitrary collinear array of sound-soft two-dimensional screens  ...  We also show how our method can be applied to the complementary "breakwater" problem of propagation through an aperture in an infinite sound-hard screen.  ...  Acknowledgements We gratefully acknowledge the support of EPSRC grant EP/F067798/1, for all authors, and of EPSRC grant EP/K000012/1, for SL.  ... 
arXiv:1401.2786v2 fatcat:gtzikf4zrzc4fbxtb6nb7xsawa

A frequency-independent boundary element method for scattering by two-dimensional screens and apertures

D. P. Hewett, S. Langdon, S. N. Chandler-Wilde
2014 IMA Journal of Numerical Analysis  
We propose and analyse a hybrid numerical-asymptotic hp boundary element method for time-harmonic scattering of an incident plane wave by an arbitrary collinear array of sound-soft two-dimensional screens  ...  We also show how our method can be applied to the complementary "breakwater" problem of propagation through an aperture in an infinite sound-hard screen.  ...  Acknowledgements We gratefully acknowledge the support of EPSRC grant EP/F067798/1, for all authors, and of EPSRC grant EP/K000012/1, for SL.  ... 
doi:10.1093/imanum/dru043 fatcat:fpis7hvvczfvdiokob3flronsi

Near-field optics theories

Christian Girard, Alain Dereux
1996 Reports on progress in physics (Print)  
The importance of such waves was ignored for a long time in optical and surface physics until the emergence of scanning near-field optical microscopes.  ...  Taking evanescent waves into account prevents the use of any simple approximation in the set of Maxwell's equations.  ...  This work was performed in the framework of the Human Capital and Mobility research network Near-Field Optics for Nanoscale Science and Technology initiated by the European Community.  ... 
doi:10.1088/0034-4885/59/5/002 fatcat:kx6l35zg4vbjxisoyyf4iovhoe

Integration of hp-adaptivity and a two grid solver for electromagnetic problems

D. Pardo, L. Demkowicz, J. Gopalakrishnan
2006 Computer Methods in Applied Mechanics and Engineering  
We present implementation details and analyze convergence of a two grid solver forming the core of a fully automatic hp-adaptive strategy for electromagnetic problems.  ...  The solver delivers a solution for a fine grid obtained from an arbitrary coarse hp grid by a global hp-refinement.  ...  Acknowledgements The work has been partially supported by Air Force under Contract F49620-01-1-0043 and NSF under Grant DMS-0410030.  ... 
doi:10.1016/j.cma.2005.05.017 fatcat:7djzlj64nbfhhcvdp5s3267psq

Physics and Computation of Aero-Optics

Meng Wang, Ali Mani, Stanislav Gordeyev
2012 Annual Review of Fluid Mechanics  
Following a brief introduction of the fundamental theory and key concepts, computational techniques for aberrating flow fields and optical propagation are discussed along with a brief survey of wave-front  ...  This article provides a critical review of aero-optics with an emphasis on recent developments in computational predictions and the physical mechanisms of flow-induced optical distortions.  ...  ACKNOWLEDGMENTS The authors acknowledge support from the Air Force Office of Scientific Research, the High Energy Laser Joint Technology Office, and the Air Force Research Laboratory for research in this  ... 
doi:10.1146/annurev-fluid-120710-101152 fatcat:txxujpdlirgldemdfjqzanpgni

A transformation approach for efficient evaluation of oscillatory surface integrals arising in three-dimensional boundary element methods

Jonathan A. Hargreaves, Yiu W. Lam, Stephen Langdon
2016 International Journal for Numerical Methods in Engineering  
SUMMARY We propose a method for efficient evaluation of surface integrals arising in boundary element methods for three-dimensional Helmholtz problems (with real positive wavenumber k/, modelling wave  ...  A., Lam, Y. W. and Langdon, S. (2016) A transformation approach for efficient evaluation of oscillatory surface integrals arising in threedimensional boundary element methods.  ...  ACKNOWLEDGEMENTS This work was supported by the UK Engineering and Physical Sciences Research Council [grant numbers EP/J022071/1 and EP/K000012/1 'Enhanced Acoustic Modelling for Auralisation using Hybrid  ... 
doi:10.1002/nme.5204 fatcat:pvx3tifwkneptngo3jhqjvbxb4

Physical optics modeling of 2D dielectric lenses

Vladimir B. Yurchenko, Ayhan Altintas
2009 Optical Society of America. Journal A: Optics, Image Science, and Vision  
For comparison, we obtain an exact full-wave solution of a two-dimensional lens problem and use it as a benchmark for testing and validation of asymptotic models being considered.  ...  We propose an advanced physical optics formulation for the accurate modeling of dielectric lenses used in quasi-optical systems of millimeter, submillimeter, and infrared wave applications.  ...  A. Murphy for useful discussions.  ... 
doi:10.1364/josaa.26.000305 pmid:19183682 fatcat:xjxbijrlrnezjhzrsai4agyfsy

An overview of full-waveform inversion in exploration geophysics

J. Virieux, S. Operto
2009 Geophysics  
Recent advances in high-performance computing and multifold/multicomponent wide-aperture and wide-azimuth acquisitions make 3D acoustic FWI feasible today.  ...  Different hierarchical multiscale strategies are designed to mitigate the nonlinearity and ill-posedness of FWI by incorporating progressively shorter wavelengths in the parameter space.  ...  In the fourth part, we review the main case studies of FWI subdivided into three categories of case studies: acoustic, multiparameter, and three dimensional.  ... 
doi:10.1190/1.3238367 fatcat:gv45siwwhvahvduawt2nd27wza
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