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Related papers: The Near Field Refractor

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In this paper we consider the problem of radiation from a vertical short Hertzian dipole above flat lossy ground, which represents the well known in the literature Sommerfeld radiation problem. The problem is formulated in a novel spectral…

Classical Physics · Physics 2014-01-09 Ch. Christakis , K. Ioannidi , S. Sautbekov , P. Frangos , S. K. Atanov

It is shown that every simple polygon in general position with $n$ walls can be illuminated from a single point light source $s$ after at most $\lfloor (n-2)/4\rfloor$ diffuse reflections, and this bound is the best possible. A point $s$…

Computational Geometry · Computer Science 2015-05-19 Eli Fox-Epstein , Csaba Tóth , Andrew Winslow

A recent paper showed how to construct a lens that focuses near field radiation and hence produce resolution unlimited by wavelength. The prescription requires lossless materials with negative refractive index: finite loss cuts off the…

Condensed Matter · Physics 2009-11-07 S. Anantha Ramakrishna , J. B. Pendry

Refraction at a smooth interface is accompanied by momentum transfer normal to the interface. We show that corrugating an initially smooth, totally reflecting, non-metallic interface provides a momentum kick parallel to the surface, which…

Other Condensed Matter · Physics 2009-11-13 W. T. Lu , Y. J. Huang , P. Vodo , R. K. Banyal , C. H. Perry , S. Sridhar

We derive certain constraints on the reflection matrix for reflection from a plane, nonmagnetic, optically anisotropic surface using a reciprocity theorem stated long ago by van de Hulst in the context of scattering of polarized light. The…

Optics · Physics 2015-05-13 Rajendra Bhandari

In this work, the properties of the radiation emitted by a corner reflector with an electric dipole feeder are analyzed in the optical domain where the distance between the dipole and the corner apex can be large in terms of the optical…

Optics · Physics 2024-01-01 Pedro Chamorro-Posada

Negative refraction is demonstrated in one-dimensional (1D) dielectric photonic crystals (PCs) at microwave frequencies. Focusing by plano-concave lens made of 1D PC due to negative refraction is also demonstrated. The frequency-dependent…

Other Condensed Matter · Physics 2009-11-11 P. Vodo , W. T. Lu , Y. Huang , S. Sridhar

Formation of a bright-field microscopic image of a transparent phase object is described in terms of elementary geometrical optics. Our approach is based on the premise that image replicates the intensity distribution (real or virtual) at…

Optics · Physics 2018-02-14 A. K. Khitrin , M. A. Model

Near-field enhancement and sub-wavelength imaging properties of a system comprising a coupled pair of two-dimensional arrays of resonant nanospheres are studied. The concept of using two coupled material sheets possessing surface mode…

Optics · Physics 2009-11-13 Pekka Alitalo , Constantin Simovski , Ari Viitanen , Sergei Tretyakov

Modern 3D reconstruction and novel view synthesis approaches have demonstrated strong performance on scenes with opaque Lambertian objects. However, most assume straight light paths and therefore cannot properly handle refractive and…

Computer Vision and Pattern Recognition · Computer Science 2025-05-19 Yue Yin , Enze Tao , Weijian Deng , Dylan Campbell

Electromagnetism in an inhomogeneous dielectric medium at rest is described using the methods of differential geometry. In contrast to a general relativistic approach the electromagnetic fields are discussed in three-dimensional space only.…

General Relativity and Quantum Cosmology · Physics 2009-11-07 Paul Piwnicki

In this paper, we show by experiment that by covering a thin flat nonlinear lens on the sources, the sub-diffraction-limit observation can be achieved by measuring either the near-field distribution or the far-field radiation of the sources…

In this paper, we study the problem of reproducing the world lighting from a single image of an object covered with random specular microfacets on the surface. We show that such reflectors can be interpreted as a randomized mapping from the…

Computer Vision and Pattern Recognition · Computer Science 2014-12-30 Zhengdong Zhang , Phillip Isola , Edward H. Adelson

The displacement of star images by atmospheric refraction observed by an Earth-bound telescope is dominated by a familiar term proportional to the product of the tangent of the zenith angle by the refractivity at the ground. The manuscript…

Instrumentation and Methods for Astrophysics · Physics 2015-03-02 Richard J. Mathar

Given near or far field wave measurements generated by some unknown time- and space-dependent acoustic source, we seek to rapidly determine a domain in space-time, as small as possible, that contains the support of a source radiating these…

Analysis of PDEs · Mathematics 2016-07-07 Armin Lechleiter

This article presents a novel undersampled magnetic resonance imaging (MRI) technique that leverages the concept of Neural Radiance Field (NeRF). With radial undersampling, the corresponding imaging problem can be reformulated into an image…

Image and Video Processing · Electrical Eng. & Systems 2024-03-05 Tae Jun Jang , Chang Min Hyun

We propose a device with a positive isotropic refractive index that creates an approximate magnified perfect real image of an optically homogeneous three-dimensional region of space within geometrical optics. Its key ingredient is a new…

Optics · Physics 2012-01-13 Tomas Tyc , Martin Sarbort

One-dimensional optical waveguiding is revisited using the electromagnetic deduction of Fresnel formulas relating the incident, reflected, and transmitted waves on the abrupt interface between two different optical media. Throughout the…

The third part of the paper is devoted to ray tracing in optical resonators. The employed method for dealing with the issue uses the elliptical or hyperbolic rotations that Wigner distributions associated with optical fields undergo during…

Optics · Physics 2022-04-01 Pierre Pellat-Finet , Éric Fogret

The inverse acoustic scattering problems using multi-frequency backscattering far field patterns at isolated directions are studied. The underlying object could be point like scatterers, small scatterers, extended inhomogeneities and…

Analysis of PDEs · Mathematics 2019-10-18 Xia Ji , Xiaodong Liu
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