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Showing papers on "Physical optics published in 2002"


Journal ArticleDOI
TL;DR: A geometric and electromagnetic model of a typical element of urban structure is presented, in order to analytically evaluate in closed form its electromagnetic return to an active microwave sensor to understand what information on geometric and dielectric properties of a building can be extracted from microwave remote sensing data.
Abstract: In this paper, a geometric and electromagnetic model of a typical element of urban structure is presented, in order to analytically evaluate in closed form its electromagnetic return to an active microwave sensor. This model can be used to understand what information on geometric and dielectric properties of a building can be extracted from microwave remote sensing data. The geometrical model consists of a rectangular parallelepiped whose vertical walls form a generic angle with respect to the sensor line of flight. The parallelepiped is placed on a rough surface. The radar return from such a structure can be decomposed into single-scattering contributions from the (rough) ground, the building roof (a plane surface in our model), and vertical walls and multiple scattering contributions from dihedral structures formed by vertical walls and ground. In our model, single-scattering contributions are evaluated by using either physical optics (PO) or geometrical optics (GO), depending on surface roughness. In order to account for multiple scattering between buildings and terrain, we use GO to evaluate the field reflected by the smooth wall toward the ground (first bounce) or the sensor (second or third bounce) and GO or PO (according to ground surface roughness) to evaluate the field scattered by the ground toward the wall (first or second bounce) or the sensor (second bounce). Finally, the above model is used to analyze the field backscattered from a building as a function of the main scene parameters; in particular, the angle between vertical walls and sensor line of night and the dependence on the look angle are analyzed.

250 citations


Journal ArticleDOI
TL;DR: It is shown that the recently discovered phenomenon of so-called spectral switches has a natural interpretation in the framework of singular optics with polychromatic light and should be regarded as being primarily a manifestation of diffraction- induced spectral changes rather than correlation-induced spectral changes.
Abstract: It is shown that the recently discovered phenomenon of so-called spectral switches has a natural interpretation in the framework of singular optics with polychromatic light and that it should be regarded as being primarily a manifestation of diffraction-induced spectral changes rather than correlation-induced spectral changes as was suggested in the original papers [the first one appearing in Opt. Commun. 162, 57 (1999)] reporting this effect.

119 citations


Journal ArticleDOI
TL;DR: In this article, the authors present an analysis of the shadowgraph method of visualizing convective flows based on physical optics, treating the refractive-index perturbation caused by the flow as a transmission grating.
Abstract: We present an analysis of the shadowgraph method of visualizing convective flows based on physical optics, treating the refractive-index perturbation caused by the flow as a transmission grating. Various patterns in thermal convection of an isotropic fluid as well as normal rolls in electroconvection of a nematic liquid crystal are considered. The results differ significantly from those of geometrical optics, showing that use of the shadowgraph as a quantitative tool for amplitude measurements should not, in general, be based on geometrical optics.

118 citations


Journal ArticleDOI
TL;DR: An S-matrix approach to open optical cavities is introduced which proves very suitable for the identification of resonances of intermediate width that will be most important in future applications like optical communication devices and it is shown that the Husimi representation is a useful tool in characterizing resonances.
Abstract: We study the dielectric annular billiard as a quantum chaotic model of a micro-optical resonator. It differs from conventional billiards with hard-wall boundary conditions in that it is partially open and composed of two dielectric media with different refractive indices. The interplay of reflection and transmission at the different interfaces gives rise to rich dynamics of classical light rays and to a variety of wave phenomena. We study the ray propagation in terms of Poincare surfaces of section and complement it with full numerical solutions of the corresponding wave equations. We introduce and develop an S-matrix approach to open optical cavities which proves very suitable for the identification of resonances of intermediate width that will be most important in future applications like optical communication devices. We show that the Husimi representation is a useful tool in characterizing resonances and establish the ray-wave correspondence in real and phase space. While the simple ray picture provides a good qualitative description of certain system classes, only the wave description reveals the quantitative details.

102 citations


Book
11 Feb 2002
TL;DR: The second edition contains 13 new chapters, covering optical pulse compression, the Hanbury Brown-Twiss experiment, the Sagnac effect, Doppler shift and stellar aberration, and optics of semiconductor diode lasers as discussed by the authors.
Abstract: Covering a broad range of fundamental topics in classical optics and electro-magnetism, this book is ideal for graduate-level courses in optics, providing supplementary reading materials for teachers and students alike. Industrial scientists and engineers developing modern optical systems will also find it an invaluable resource. Now in color, this second edition contains 13 new chapters, covering optical pulse compression, the Hanbury Brown-Twiss experiment, the Sagnac effect, Doppler shift and stellar aberration, and optics of semiconductor diode lasers. The first half of the book deals primarily with the basic concepts of optics, while the second half describes how these concepts can be used in a variety of technological applications. Each chapter is concerned with a single topic, developing an understanding through the use of diagrams, examples, numerical simulations, and logical arguments. The mathematical content is kept to a minimum to provide the reader with insightful discussions of optical phenomena.

96 citations


Journal ArticleDOI
14 Mar 2002-Nature
TL;DR: Nonlinear atom optics progress culminated in the demonstration of phase-coherent matter-wave amplification; a first step in this area is the measurement of reduced number fluctuations in a Bose–Einstein condensate partitioned into a series of optical potential wells.
Abstract: Coherent matter waves in the form of Bose-Einstein condensates have led to the development of nonlinear and quantum atom optics - the de Broglie wave analogues of nonlinear and quantum optics with light. In nonlinear atom optics, four-wave mixing of matter waves and mixing of combinations of light and matter waves have been observed; such progress culminated in the demonstration of phase-coherent matter-wave amplification. Solitons represent another active area in nonlinear atom optics: these non-dispersing propagating modes of the equation that governs Bose-Einstein condensates have been created experimentally, and observed subsequently to break up into vortices. Quantum atom optics is concerned with the statistical properties and correlations of matter-wave fields. A first step in this area is the measurement of reduced number fluctuations in a Bose-Einstein condensate partitioned into a series of optical potential wells.

92 citations


Journal ArticleDOI
TL;DR: In this paper, an interferometric technique for analysis of a polarization singular skeleton (s contours and C points) of an optical vector field is elaborated, and complete characteristics of C points and s contours may be reconstructed from interferometrical data.
Abstract: An interferometric technique for analysis of a polarization singular skeleton (s contours and C points) of an optical vector field is elaborated. It was shown that complete characteristics of C points and s contours may be reconstructed from interferometric data. Some examples of elaborated interferometric technique application to the analysis of randomly polarized speckle-fields singularities are presented.

74 citations


Journal ArticleDOI
TL;DR: Both ray optics analysis and wave optics analysis confirm that the double-device integral imaging systems can pick up and display images at two separate image planes.
Abstract: By adoption of double-device systems, integral imaging can be enhanced in image depth, viewing angle, or image size. Theoretical analyses are done for the double-image-plane integral imaging systems. Both ray optics analysis and wave optics analysis confirm that the double-device integral imaging systems can pick up and display images at two separate image planes. The analysis results are also valuable in the understanding of the conventional integral imaging systems for image positions off the central depth plane.

68 citations


Journal ArticleDOI
P. Pouliguen, L. Lucas1, F. Muller1, S. Quete1, C. Terret1 
TL;DR: In this paper, the authors describe an application of physical optics and the method of equivalent currents to the calculation of radar cross section (RCS) of a helicopter rotor using a quasi-stationary approach.
Abstract: This paper describes an application of physical optics and the method of equivalent currents to the calculation of radar cross section (RCS) of a helicopter rotor. The problem is treated using a quasi-stationary approach. The calculation can be parameterized as a function of the locations of the radar transmitter and receiver in relation to the rotor center. Therefore, this offers the possibility of monostatic and bistatic simulations in the far field and near field. Blade geometry is taken into account using a triangular meshing generated by the I-DEAS meshing software. Digital applications are presented and the effects on the RCS spectrum of incidence, frequency, blade number, and the near field are analyzed.

64 citations


Journal ArticleDOI
TL;DR: In this paper, a set of experiments with the aim of studying for the first time relativistic nonlinear optics in the fundamental limits of single-cycle pulse duration and single-wavelength spot size is presented.
Abstract: We propose a set of experiments with the aim of studying for the first time relativistic nonlinear optics in the fundamental limits of single-cycle pulse duration and single-wavelength spot size. The laser sys- tem that makes this work possible is now operating at the Center for Ultrafast Optical Science at the University of Michigan. Its high repetition rate (1 kHz) will make it possible to perform a detailed investigation of relativ- istic effects in this novel regime. This study has the potential to make the field of relativistic optics accessible to a wider community and to open the door for real-world applications of relativistic optics, such as electron/ion acceleration and neutron and positron production. © 2002 MAIK "Nauka/Interperiodica".

64 citations



Proceedings ArticleDOI
04 Sep 2002
TL;DR: The Synchrotron Radiation Workshop (SRW) as mentioned in this paper is a physical optics computer code optimized for the simulation of emission and propagation of coherent and partially-coherent synchron radiation.
Abstract: Synchrotron Radiation Workshop (SRW) - a physical optics computer code optimized for the simulation of emission and propagation of coherent and partially-coherent synchrotron radiation is presented. The code consists of two parts, which can be used independently. One part is dedicated to the computation of electric field, intensity, spectral-angular characteristics of radiation emitted by relativistic electrons in undulators, wigglers, short magnets, etc. The other part of the code implements physical optics methods for wavefront propagation. The propagation in free space is made according to the Huygens-Fresnel principle, by means of a prime-factor 2D FFT. Normal-incident optical elements are described by a complex transmission function. Fast algorithm for the propagation of electro-magnetic field through simple waveguides is implemented. The propagation of partially-coherent radiation is done by summing up contributions to the final intensity from different sources (e.g. from distinct emitting electrons), taking into account the sources' properties and applying, when possible, the convolution theorem with respect to intensity. SRW code can be used for physical optics simulations, design and optimization of refractive and diffractive optical elements for various spectral ranges, from far infrared to hard X-rays.

Journal ArticleDOI
J.R. Kurz1, A.M. Schober1, D.S. Hum1, A.J. Saltzman1, Martin M. Fejer1 
TL;DR: In this paper, the amplitude and phase of a second-harmonic beam in multiple slit diffraction devices and in quasi-phase-matching (QPM) lenses are demonstrated.
Abstract: Transverse patterning of periodic gratings for quasi-phase-matching (QPM) at the micron scale leads to a multitude of nonlinear optical devices based on familiar physical optics effects. We demonstrate spatial control over the amplitude and phase of a second-harmonic beam in multiple slit diffraction devices and in QPM lenses, which are nonreciprocal devices.

Journal ArticleDOI
Amir Boag1
TL;DR: In this article, a fast iterative physical optics (FIPO) algorithm is proposed for analysis of scattering from electrically large objects involving multiple reflections such as the case for open-ended cavities.
Abstract: In this paper, a novel fast iterative physical optics (FIPO) algorithm is proposed for analysis of scattering from electrically large objects involving multiple reflections such as the case for open-ended cavities. At each iteration, the physical optics current induced on the surface of the scatterer produces a correction to the incident field, which in turn induces a correction to the physical optics current. The FIPO algorithm relies on fast field evaluation, which is achieved via domain decomposition of the scatterer surface and comprises two steps repeated for each subdomain. First, computation of the field is produced by currents residing within a subdomain over a sparse set of points surrounding the scatterer. Second, phase removal, interpolation, phase restoration, and aggregation of the field of the subdomain are integrated into the total field on the surface. The proposed approach can be extended to fast iterative solution of problems discretized via the method of moments. © 2002 Wiley Periodicals, Inc. Microwave Opt Technol Lett 35: 240–244, 2002; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10568

Journal ArticleDOI
TL;DR: A computer program of this type is most useful in situations in which the base station (BS) antenna is above local clutter, and over areas large enough that ground cover can be characterized with categories such as "open," "forest," "dense residential," etc., rather than individual buildings.
Abstract: Physical optics, or Fresnel-Kirchhoff theory, is often used for studies of particular problems in terrestrial radio-wave propagation. With efficient techniques of numerical integration, it can also be used effectively for routine predictions and for designing terrestrial wireless systems. A computer program of this type has been in use for several years. It is most useful in situations in which the base station (BS) antenna is above local clutter, and over areas large enough that ground cover can be characterized with categories such as "open," "forest," "dense residential," etc., rather than individual buildings. The main calculation is a marching algorithm that simulates diffraction over all the variations in terrain height along radials from the BS. A secondary calculation estimates the additional attenuation due to buildings and trees close to the mobile antenna. This part of the calculation is based on several parameters characterizing the local environment of the mobile antenna. Calculations are slow compared to many traditional methods, but are fast enough for routine use on a PC.

Journal ArticleDOI
TL;DR: In this article, an analytical theory of resonance diffraction in the conical mount is presented, where the resonance is caused by plasmon polariton excitation via diffraction from a high reflecting shallow grating.
Abstract: This paper presents an analytical theory of resonance diffraction in the conical mount. The resonance is caused by plasmon polariton excitation via diffraction from a high reflecting shallow grating. The dependence of polarization, intensity, and phase of specular and resonance waves on the parameters of the problem is presented in explicit form and examined for arbitrary polarization of the incident wave as a function of the angle of incidence and the grating period, orientation and depth. The results obtained enable us to indicate gratings with specific properties, for instance, gratings, ensuring transformation of arbitrarily polarized incident wave into the linearly polarized specular wave. The properties of two-dimensional transformation matrix relating polarization amplitudes of the incident and the specular reflected waves are analyzed. It is shown that the transformation matrix is antisymmetric (in accordance with the reciprocity theorem) for an arbitrary grating profile in the main approximation. The comparison of the results obtained shows remarkable agreement (with-out any parameters fitting!) with data of the polarization conversion experiments. Both concrete results and the approach presented may be of use in constructing gratings with the predetermined parameters and, therefore, in solving problems of designing optical devices selective with respect to the polarization, wavelength, and orientation.

Journal ArticleDOI
TL;DR: The low-grazing-angle (LGA) backscattering from one-dimensionally rough surface profiles approximating breaking water waves with roughened front faces has been numerically examined and a good prediction of both the coherent and incoherent scattering coefficients is given.
Abstract: The low-grazing-angle (LGA) backscattering from one-dimensionally rough surface profiles approximating breaking water waves with roughened front faces has been numerically examined. The added front-face roughness approximates that expected from wind generation. The reference "exact" backscattering was found using a numerical technique based on the moment method. A model-based approach to predict the backscattering was also implemented. In this, the crest scattering was found directly using the moment method, the multipath scattering was modeled using physical optics, and the distributed-surface scattering from the small-scale roughness was found from the two-scale model. The calculations show that the roughness adds incoherent components to both the vertically (VV) and horizontally (HH) polarized scattering cross sections. At VV, this is due to the random scattering from the small-scale roughness, while at HH it results from random changes in the multipath interference due to the large-scale roughness. As the mechanisms for the incoherent scattering are independent, it is difficult to predict the magnitude of the HH-to-VV backscattering ratio that will occur with specific realizations of the roughness from the underlying breaking-wave shape alone, particularly with large rms roughness added. Overall, the model-based calculations give a good prediction of both the coherent and incoherent scattering coefficients.

Journal ArticleDOI
TL;DR: In this paper, the authors focus on the spectroscopic applications of optical parametric oscillators in the sensing of chemical processes, in industrial or environmental diagnostics, and in basic optical physics.
Abstract: This article focuses on the spectroscopic applications of optical parametric oscillators in the sensing of chemical processes, in industrial or environmental diagnostics, and in basic optical physics.

Journal ArticleDOI
TL;DR: In this article, backprojection tomography is applied to form two-dimensional (2D) synthetic aperture radar images from deterministic surface scattered field data at multiple incidence angles and frequencies.
Abstract: Rough surface scattering theories are investigated through analysis of radar images. Backscatter results from 10 GHz to 14 GHz under tapered wave illumination are considered for one-dimension (1D) random rough surface realizations which satisfy an impedance boundary condition. Back-projection tomography is applied to form two-dimensional (2D) synthetic aperture radar images from deterministic surface scattered field data at multiple incidence angles and frequencies. Numerical predictions of surface backscattered fields are obtained from an accelerated forward-backward (FB) method and the resulting images are compared with those obtained from approximate scattering theories such as the physical optics (PO) approximation, the small slope approximation (SSA), and the nonlocal SSA (NLSSA). The resulting radar images illustrate scattering sources associated with single and multiple scattering on the boundary, and a ray tracing analysis confirms the locations of time-delayed image points due to double reflections. For single scattering effects, the images demonstrate excellent agreement between analytical and numerical methods in both horizontal and vertical polarizations. For surfaces with RMS height 2.0 cm and correlation length 7.5 cm at normal incidence, multiple-scattering effects are observed and successfully captured when the lowest-order NLSSA is employed.

Journal ArticleDOI
TL;DR: In this paper, an experimental analysis of the phase of the scattered field from a patch embedded in an array environment has been presented, where the phase relation is calculated by a standard commercial full wave code, saving a large amount of computational time.
Abstract: sEarr s Egrp s where Earr and Egrp are the fields scattered from the array of microstrip patches and from the finite ground plane, respectively. The first term is computed with the use of the MoM code, and the second is evaluated with the physical optics theory. The results given by this method (crossed curve) are in good agreement with the measured ones. 3. CONCLUSIONS In this Letter an experimental analysis of the phase of the scattered field from a patch embedded in an array environment has been presented. An hybrid moment method—physical optics technique has been proved to be an effective method of analysis with a reduced computational effort. This approach permits the phase relation to be calculated by a standard commercial full wave code, saving a large amount of computational time.

Proceedings ArticleDOI
06 Feb 2002
TL;DR: In this article, the authors describe the purpose, theory, implementation and sample results of a wave optics propagation simulation developed to study multi-conjugate adaptive optics (MCAQ) for 4-10m class telescopes.
Abstract: We describe the purpose, theory, implementation and sample results of a wave optics propagation simulation developed to study multi-conjugate adaptive optics (MCAQ) for 4-10m class telescopes. This code was more specifically developed to assess the impact of diffraction effects and a variety of implementation error sources upon the performance of the Gemini-South MCAO system. These errors include: Hartmann sensing with extended and elongated laser guide stars, optical propagation effects through the optics and atmosphere, laser guide star (LGS) projection through the atmosphere, deformable mirror (DM) and wave front sensor (WFS) misregistration, and calibration for non-common path errors. The code may be run in either a wave optics or geometric propagation mode to allow the code to be anchored against linear analytical models and to explicitly evaluate the impact of diffraction effects. The code is written in MATLAB, and complete simulations of the Gemini-South MCAO design (including 3 deformable mirrors with 769 actuators, 5 LGS WFS with 1020 subapertures, 3 tip/tilt natural guide star (NGS) WFS, and 50 meter phase screens with 1/32nd meter resolution) are possible using a Pentium III but require 1 to 6 days. Sample results are presented for Gemini-South MCAO as well as simpler AO systems. Several possibilities for parallelizing the code for faster execution and the modeling of extremely large telescopes (ELT's) are discussed.

Journal ArticleDOI
TL;DR: In this paper, a plane wave incidence by an array of perfectly conducting wedges is proposed, where the source is assumed to be above, below, or level with the edge height.
Abstract: In this paper, a formulation for plane wave incidence by an array of perfectly conducting wedges is proposed. The solution takes the advantages of the uniform theory of diffraction (UTD) and physical optics (PO), and allows for numerical evaluation of a large number of perfectly conducting wedges. The solution has the major advantage of shortening the computing time over existing formulation when the number of wedges is very large. The source is assumed to be above, below, or level with the edge height. The technique proposed is validated with numerical results from technical literature. Results for cases not previously reported in the technical literature are also presented.

Journal ArticleDOI
TL;DR: In this article, a detailed characterization of the intricate high-frequency whispering-gallery (WG) mode-to-beam conversion is presented for the two-dimensional case, and a comprehensive asymptotic theory for the induced surface currents on the boundary as well as the near and far fields generated by them is presented.
Abstract: When a well-confined high-frequency (HF) whispering-gallery (WG) mode launched from the concave side of a concave-convex perfectly conducting boundary propagates toward the convex side, it becomes successively less confined and eventually detaches completely to form a radiated beam field. Detailed characterization of the intricate WG mode-to-beam conversion (here considered for the two-dimensional case) poses a challenging problem in HF wave propagation and asymptotics. This paper begins with a review of the accomplishments and shortcomings in previous investigations that dealt with the analytic-asymptotic aspects as well as the construction of numerical reference solutions to validate the HF approximations. We then develop algorithms based upon the earlier results, but with inclusion of new refinements. These yield a comprehensive asymptotic theory for the induced surface currents on the boundary as well as the near and far fields generated by them, well-matched to the WG mode detachment phenomenology and numerically accurate when compared with reference data obtained from a new hybrid analytic-numerical code. The asymptotic analysis makes use of Kirchhoff, physical optics, and spectral integral representations, WG modes on the concave side, modal ray tracing, replacing modal and/or ray caustics by equivalent induced source distributions, creeping waves on the convex side, etc., with self-consistent blending of nonuniform and locally uniform asymptotics through transition regions where transformations of the affected wavefields occur.

Book
06 Dec 2002
TL;DR: Imaging Using Wave Theory using Fourier Transformation and FT-Spectroscopy for image analysis of blackbody radiation, Atomic Emission and Laseras.
Abstract: Geometrical Optics * Interference * Diffraction * Coherence * Maxwell's Theory * Maxwell II. Modes and Mode Propagation * Blackbody Radiation, Atomic Emission and Lasers * Optical Constants * Fourier Transformation and FT-Spectroscopy * Imaging Using Wave Theory * Aberration.

Proceedings ArticleDOI
J.R. Kurz1, A.M. Schober1, D.S. Hum1, A.J. Saltzman1, Martin M. Fejer1 
24 May 2002
TL;DR: Transverse patterning of periodic gratings for quasi-phase matching (QPM) has been used to increase the tuning range of devices (through fanned gratings), to shape the amplitude profile of an interacting beam, and to create two-dimensional periodic QPM structures (nonlinear photonic crystals) for efficient noncollinear mixing as mentioned in this paper.
Abstract: Summary from only given. Transverse patterning of periodic gratings for quasi-phase- matching (QPM) has been used to increase the tuning range of devices (through fanned gratings), to shape the amplitude profile of an interacting beam, and to create two-dimensional periodic QPM structures (nonlinear photonic crystals) for efficient noncollinear mixing.

Posted Content
TL;DR: The analogy between geometrical optics and the classical theories of charged-particle beam optics has been known for a very long time as discussed by the authors, and with the current development of non-traditional prescriptions of Helmholtz and Maxwell, accompanied with the wavelength-dependent effects, it is seen that the analogy between the two systems persists.
Abstract: The close analogy between geometrical optics and the classical theories of charged-particle beam optics have been known for a very long time. In recent years, quantum theories of charged-particle beam optics have been presented with the very expected feature of wavelength-dependent effects. With the current development of non-traditional prescriptions of Helmholtz and Maxwell optics respectively, accompanied with the wavelength-dependent effects, it is seen that the analogy between the two systems persists. A brief account of the various prescriptions and the parallel of the analogies is presented.

Journal ArticleDOI
TL;DR: In this paper, a numerical model that allows us to calculate the contribution of a specified scattering order in the geometric optics approximation for media composed of large particles with an arbitrary phase function is presented, showing that the correlated propagation of the incident and emergent rays, which is disregarded in the classical radiative transfer theory, markedly affects the contributions of different orders of scattering.
Abstract: We present a numerical model that allows us to calculate the contribution of a specified scattering order in the geometric optics approximation for media composed of large particles with an arbitrary phase function It has been demonstrated that the correlated propagation of the incident and emergent rays, which is disregarded in the classical radiative-transfer theory, markedly affects the contributions of different orders of scattering, especially the first-order scattering If the theory describing the photometric properties of regolith-like media ignores the shadowing effect, the errors of its application may reach several tens of percent even for bright surfaces The packing density of a medium essentially influences the phase dependence of the first-order scattering, although its effect on the value and the phase curve of the higher scattering orders is relatively weak The backscattering peaks calculated on the basis of the Hapke theory are narrower than those obtained from the numerical simulations, because the Hapke theory is an approximate approach

Journal ArticleDOI
TL;DR: In this article, the effective geometry seen by electromagnetic waves propagating in media whose physical properties depend on an external electric field was derived by working with electrodynamics in the geometrical optics approximation.
Abstract: Working with electrodynamics in the geometrical optics approximation, we derive the expression representing the "effective geometry" seen by electromagnetic waves propagating in media whose physical properties depend on an external electric field. Some previous results are generalized and some special cases are recovered.

Journal ArticleDOI
TL;DR: It is shown that the two theories produce identical results for "long wave" contributions to sea emission azimuthal variations up to third order in long wave surface slope when shadowing effects are neglected.
Abstract: A comparison of the physical optics and small slope theories of emission from the sea surface is described. It is shown that the two theories produce identical results for "long wave" contributions to sea emission azimuthal variations up to third order in long wave surface slope when shadowing effects are neglected.

Journal ArticleDOI
TL;DR: In this paper, the boundary problem of linear classical optics about the interaction of electromagnetic radiation with a thin dielectric film has been solved under explicit consideration of its discrete structure, and it is shown by means of analytical and numerical calculations that due to the existence of the evanescent harmonics the laws of reflection and refraction at the distances from the surface less than two interatomic distances are principally different from the Fresnel laws.
Abstract: The boundary problem of linear classical optics about the interaction of electromagnetic radiation with a thin dielectric film has been solved under explicit consideration of its discrete structure. The main attention has been paid to the investigation of the near-zone optical response of dielectrics. The laws of reflection and refraction for discrete structures in the case of a regular atomic distribution are studied and the structure of evanescent harmonics induced by an external plane wave near the surface is investigated in details. It is shown by means of analytical and numerical calculations that due to the existence of the evanescent harmonics the laws of reflection and refraction at the distances from the surface less than two interatomic distances are principally different from the Fresnel laws. From the practical point of view the results of this work might be useful for the near-field optical microscopy of ultrahigh resolution.