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Related papers: Focussing Light Using Negative Refraction

200 papers

Inverse rendering of glossy objects from RGB imagery remains fundamentally limited by inherent ambiguity. Although NeRF-based methods achieve high-fidelity reconstruction via dense-ray sampling, their computational cost is prohibitive.…

Computer Vision and Pattern Recognition · Computer Science 2025-08-21 Xingyuan Yang , Min Wei

We consider the non-line-of-sight (NLOS) imaging of an object using the light reflected off a diffusive wall. The wall scatters incident light such that a lens is no longer useful to form an image. Instead, we exploit the 4D spatial…

Computer Vision and Pattern Recognition · Computer Science 2022-12-06 Andre Beckus , Alexandru Tamasan , George K. Atia

Casual photography is often performed in uncontrolled lighting that can result in low quality images and degrade the performance of downstream processing. We consider the problem of estimating surface normal and reflectance maps of scenes…

Computer Vision and Pattern Recognition · Computer Science 2020-12-14 Zhihao Xia , Jason Lawrence , Supreeth Achar

We demonstrate that light is subject to anomalous (i.e., negative) diffraction when propagating in the presence of hyperbolic dispersion. We show that light propagation in hyperbolic media resembles the dynamics of a quantum particle of…

A number of design options for image slicers for NGST and Gemini are being investigated. These image slicers are all of the focussing type and both refractive and reflective solutions are being explored. One such device, an image slicer…

Astrophysics · Physics 2007-05-23 E. H. Richardson , A. Moore , T. Tilleman , David Crampton

As light travels through a disordered medium such as biological tissues, it undergoes multiple scattering events. This phenomenon is detrimental to in-depth optical microscopy, as it causes a drastic degradation of contrast, resolution and…

Recovering the shape and reflectance of non-Lambertian surfaces remains a challenging problem in computer vision since the view-dependent appearance invalidates traditional photo-consistency constraint. In this paper, we introduce a novel…

Computer Vision and Pattern Recognition · Computer Science 2019-04-22 Mingyuan Zhou , Yu Ji , Yuqi Ding , Jinwei Ye , S. Susan Young , Jingyi Yu

We define compactness of a gravitational lens as the scaled closest distance of approach (i.e., $r_0/M$) of the null geodesic giving rise to an image. We model forty supermassive dark objects as Schwarzschild lenses and compute compactness…

General Relativity and Quantum Cosmology · Physics 2024-08-13 K. S. Virbhadra

We introduce a novel learning-based method to reconstruct the high-quality geometry and complex, spatially-varying BRDF of an arbitrary object from a sparse set of only six images captured by wide-baseline cameras under collocated point…

Computer Vision and Pattern Recognition · Computer Science 2020-07-07 Sai Bi , Zexiang Xu , Kalyan Sunkavalli , David Kriegman , Ravi Ramamoorthi

Transformation optics aims to identify artificial materials and structures with desired electromagnetic properties by means of pertinent coordinate transformations. In general, such schemes are meant to appropriately tailor the constitutive…

De-diffraction (DD), a new procedure to totally cancel diffraction effects from wave-fields is presented, whereby the full field from an aperture is utilized and a truncated geometrical field is obtained, allowing infinitely sharp focusing…

General Physics · Physics 2007-05-23 V. F. Tamari

If an extended source, such as a galaxy, is gravitationally lensed by a massive object in the foreground, the lensing distorts the observed image. It is straightforward to simulate what the observed image would be for a particular lens and…

Astrophysics · Physics 2009-11-13 Brendon J. Brewer , Geraint F. Lewis

This paper describes a novel approach to partially reconstruct high-resolution 4D light fields from a stack of differently focused photographs taken with a fixed camera. First, a focus map is calculated from this stack using a simple…

Computer Vision and Pattern Recognition · Computer Science 2015-03-09 A. Mousnier , E. Vural , C. Guillemot

We design lenses composed of a combination of standard freeform refracting surface and flat metasurface refracting an arbitrary incident field into a collimated beam with a fixed direction. In the near-field case, we study the existence of…

Analysis of PDEs · Mathematics 2023-12-29 I. Amro , F. Fneish , R. Kansoh , A. Sabra , W. Tabbara

The double diffraction of white light can produce a thin-prism-like image in certain conditions by using ordinary diffraction gratings. The diffractive deviation of rays happens mainly in one direction because the diffracting elements are…

Optics · Physics 2007-05-23 Jose J Lunazzi , Noemi I Rodriguez Rivera

Ghost projection is the reversed process of computational classical ghost imaging that allows any desired image to be synthesized using a linear combination of illuminating patterns. Typically, physical attenuating masks are used to produce…

Optics · Physics 2025-12-01 James A. Monro , Andrew M. Kingston , David M. Paganin

A resolution-enhanced dark-field microscope by structured light illumination is proposed to improve resolution and contrast. A set of phase-shifted fringes are projected to the sample plane at large angle to capture modulated dark-field…

Image and Video Processing · Electrical Eng. & Systems 2022-02-14 Shaobai Li , Bofan Song , Rongguang Liang

The concept of negative refraction is attracting a lot of attention. The initial ideas and the misconceptions that have arisen are discussed in sufficient detail to understand the conceptual structure that binds negative refraction to the…

Materials Science · Physics 2007-05-23 Allan D. Boardman , Neil King , Larry Velasco

This is the second article in a series of two dealing with the concept of "resonant metalens" we introduced recently [Phys. Rev. Lett. 104, 203901 (2010)]. It is a new type of lens capable of coding in time and radiating efficiently in the…

Optics · Physics 2016-06-29 Fabrice Lemoult , Geoffroy Lerosey , Mathias Fink

Passive optical elements can play key roles in photonic applications such as plasmonic integrated circuits. Here we experimentally demonstrate passive gap-plasmon focusing and routing in two-dimensions. This is accomplished using a high…