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Related papers: Optical Conformal Mapping and Dielectric Invisibil…

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In the past years quasi-conformal mapping has been typically used to design broadband electromagnetic cloaks. However, this technique has some inherit practical limitations such as the lateral beam shift, rendering the device visible or…

Optics · Physics 2013-11-25 Yungui Ma , Yichao Liu , Lu Lan , Tiantian Wu , Wei Jiang , C. K. Ong , Sailing He

Perfect imaging has been believed to rely on negative refraction, but here we show that an ordinary positively-refracting optical medium may form perfect images as well. In particular, we establish a mathematical proof that Maxwell's fish…

Optics · Physics 2009-09-30 Ulf Leonhardt

A zero index metamaterial (ZIM) can be utilized to block wave (super-reflection) or conceal objects completely (cloaking). The "super-reflection" device is realized by a ZIM with a perfect electric (magnetic) conductor inclusion of…

Classical Physics · Physics 2015-05-13 Jiaming Hao , Wei Yan , Min Qiu

Perfect lensing using negative refractive index materials and radiationless electromagnetic interference both provide extreme subwavelength focusing by "amplifying" evanescent wave components that are usually lost. This paper provides a…

Optics · Physics 2015-06-03 Reuven Gordon

It is hard for us humans to recognize things in nature until we have invented them ourselves. For image-forming optics, nature has made virtually every kind of lens humans have devised. But what about lensless "imaging"? Recently, we showed…

Optics · Physics 2007-05-23 Leonid Yaroslavsky , H. John Caulfield

Sub-wavelength diffractive optics meta-optics present a multi-scale optical system, where the behavior of constituent sub-wavelength scatterers, or meta-atoms, need to be modelled by full-wave electromagnetic simulations, whereas the whole…

Object detection is a crucial task in computer vision that aims to identify and localize objects in images or videos. The recent advancements in deep learning and Convolutional Neural Networks (CNNs) have significantly improved the…

Computer Vision and Pattern Recognition · Computer Science 2023-04-12 Hrishitva Patel

Data protection methods like cryptography, despite being effective, inadvertently signal the presence of secret communication, thereby drawing undue attention. Here, we introduce an optical information hiding camera integrated with an…

Optics · Physics 2024-06-13 Bijie Bai , Ryan Lee , Yuhang Li , Tianyi Gan , Yuntian Wang , Mona Jarrahi , Aydogan Ozcan

In this letter, we propose a conceptual device to perform subwavelength imaging with positive refraction. The key to this proposal is that a drain is no longer a must for some cases. What's more, this device is an isotropic omnidirectional…

Optics · Physics 2015-06-05 Qiannan Wu , Yadong Xu , Huanyang Chen

It is generally believed that transformation optics based cloaking, besides rendering the cloaked region invisible to detection by scattering of incident waves, also shields the region from those same waves. We demonstrate a coupling…

Optics · Physics 2016-05-13 Allan Greenleaf , Yaroslav Kurylev , Matti Lassas , Gunther Uhlmann

In absence of a lens to form an image, incoherent or partially coherent light scattering off an obstructive or reflective object forms a broad intensity distribution in the far field with only feeble spatial features. We show here that…

An approach to hiding objects levitating or flying above a conducting sheet is suggested in this letter. The proposed device makes use of isotropic negative-refractive-index materials without extreme material parameters, and creates an…

Optics · Physics 2010-09-29 Jingjing Zhang , Yu Luo , Niels Asger Mortensen

Diffraction is a fundamental property of light propagation. Owing to this phenomenon,light diffracts out in all directions when it passes through a subwavelength slit.This imposes a fundamental limit on the transverse size of a light beam…

Optics · Physics 2013-10-11 S. V. Kukhlevsky , M. Mechler

Light emitting diodes have superior performance over most other light sources, but the need for secondary optics to shape their illumination for specific applications yield bulky lighting products. Here, we present an approach to shaping…

Optical bistability, the basic nonlinear phenomenon mediating the control of light by light, paves the way to the all-optical logic being of ultimate demand for a plethora of applications in laser information technologies. The desirable…

Optics · Physics 2019-12-20 Denis Novitsky , Alexander Shalin

Optical imaging relies on the ability to illuminate an object, collect and analyze the light it scatters or transmits. Propagation through complex media such as biological tissues was so far believed to degrade the attainable depth as well…

Optics · Physics 2010-09-24 S. M. Popoff , G. Lerosey , M. Fink , A. C. Boccara , S. Gigan

It is a fundamental fact of waves that they spread as they evolve freely, regardless of their nature. Previous research to overcome diffraction spreading has led to idealized waves that, in real settings, exhibit quasi-non-diffraction and…

We propose a design for an universal absorber, characterized by a resonance frequency that can be tuned from visible to microwave frequencies independently of the choice of the metal and the dielectrics involved. An almost resonant perfect…

Invisibility devices exploit ambiguities in the inverse scattering problem of light in media. Scattering also serves as an important general tool to infer information about the structure of matter. We elucidate the nature of scattering…

Materials Science · Physics 2009-11-11 Awatif Hendi , Julian Henn , Ulf Leonhardt

In optical devices like diffraction gratings and Fresnel lenses, light wavefront is engineered through the structuring of device surface morphology, within thicknesses comparable to the light wavelength. Fabrication of such diffractive…

Optics · Physics 2021-07-28 S. L. Oscurato , F. Reda , M. Salvatore , F. Borbone , P. Maddalena , A. Ambrosio