English
Related papers

Related papers: Imagerie laser

200 papers

An ideal imaging system provides a spatial resolution that is ultimately dictated by the numerical aperture (NA) of the illumination and collection optics. In biological tissue, resolution is further affected by scattering limiting the…

Lenses that can collect the perfect image of an object must restore propagative and evanescent waves. However, for efficient information transfer, e.g., in compressed sensing, it is often desirable to detect only the fast spatial variations…

Optics · Physics 2016-02-01 Miguel Molerón , Chiara Daraio

Based on transformation optics, a strategy is proposed to expose the inner one-dimensional space of a wave field inside a beam volume to the surface of the propagation medium and extend the space from one-dimensional to two-dimensional,…

Optics · Physics 2020-02-24 Jiangchao Shi , Xiaobo Yang , Jin Hu

Multiple light scattering hampers imaging objects in complex scattering media. Approaches used in real practices mainly aim to filter out multiple scattering obscuring the ballistic waves that travel straight through the scattering medium.…

This paper addresses the problem of reconstructing the surface shape of transparent objects. The difficulty of this problem originates from the viewpoint dependent appearance of a transparent object, which quickly makes reconstruction…

Image and Video Processing · Electrical Eng. & Systems 2021-05-24 Kai Han , Kwan-Yee K. Wong , Miaomiao Liu

Limited-angle tomography is a highly ill-posed linear inverse problem. It arises in many applications, such as digital breast tomosynthesis. Reconstructions from limited-angle data typically suffer from severe stretching of features along…

Image and Video Processing · Electrical Eng. & Systems 2022-04-22 Siiri Rautio , Rashmi Murthy , Tatiana A. Bubba , Matti Lassas , Samuli Siltanen

Inverse source problems are central to many applications in acoustics, geophysics, non-destructive testing, and more. Traditional imaging methods suffer from the resolution limit, preventing distinction of sources separated by less than the…

Machine Learning · Computer Science 2022-08-11 Adar Kahana , Symeon Papadimitropoulos , Eli Turkel , Dmitry Batenkov

We propose an approach to far-field optical imaging beyond the diffraction limit. The proposed system allows image magnification, is robust with respect to material losses and can be fabricated by adapting existing metamaterial technologies…

Optics · Physics 2009-11-13 Zubin Jacob , Leonid V. Alekseyev , Evgenii Narimanov

A transformation optics approach was used to derive a general method for designing electromagnetic devices able to manipulate the wave vectors in the specific manner required by the functionality of the device. While the wave paths inside…

Optics · Physics 2017-07-19 Mircea Giloan

We report on experimental and numerical implementations of devices based on the negative refraction of elastic guided waves, the so-called Lamb waves. Consisting in plates of varying thickness, these devices rely on the concept of…

We propose an approach for super-resolution optical lithography which is based on the inverse of magnetic resonance imaging (MRI). The technique uses atomic coherence in an ensemble of spin systems whose final state population can be…

Quantum Physics · Physics 2015-05-19 Fahad AlGhannam , Philip Hemmer , Zeyang Liao , M. Suhail Zubairy

The far-field pattern of a simple one-dimensional laser array of emitters radiating into free space is considered. In the path of investigating the inverse problem for their near fields leading to a target beam form, surprisingly we found…

Optics · Physics 2017-08-02 Constantinos A. Valagiannopoulos , Vassilios Kovanis

Digital imaging sensor technology has continued to outpace development in optical technology in modern imaging systems. The resulting quality loss attributable to lateral chromatic aberration is becoming increasingly significant as sensor…

Computer Vision and Pattern Recognition · Computer Science 2021-10-11 Daniel J. Blueman

We consider the problem of imaging extended reflectors in terminating waveguides. We form the image by back-propagating the array response matrix projected on the waveguide's non-evanescent modes. The projection is adequately defined for…

Computational Physics · Physics 2017-11-30 Chrysoula Tsogka , Dimitrios A. Mitsoudis , Symeon Papadimitropoulos

Laser Doppler holography (LDH) is an interferometric blood flow imaging technique based on full-field measurements of the Doppler spectrum. LDH has so far been demonstrated in the retina with ultrafast cameras, typically at 75 kHz. We show…

Image and Video Processing · Electrical Eng. & Systems 2020-08-26 Leo Puyo , Michel Paques , Michael Atlan

The improvements in spectral and spatial resolution of the satellite images have facilitated the automatic extraction and identification of the features from satellite images and aerial photographs. An automatic object extraction method is…

Computer Vision and Pattern Recognition · Computer Science 2014-05-26 S. K. Katiyar , P. V. Arun

We introduce a probabilistic approach to ptychographic reconstruction in computational imaging. Ptychography is an imaging method where the complex amplitude of an object is estimated from a sequence of diffraction measurements. We…

Applications · Statistics 2025-04-09 Hajime Ueda , Shun Katakami , Masato Okada

Ultrasound reflection tomography is widely used to image large complex specimens that are only accessible from a single side, such as well systems and nuclear power plant containment walls. Typical methods for inverting the measurement rely…

Image and Video Processing · Electrical Eng. & Systems 2018-10-01 Hani Almansouri , S. V. Venkatakrishnan , Gregery T. Buzzard , Charles A. Bouman , Hector Santos-Villalobos

Like light, gravitational waves can be gravitationally lensed by massive objects along their travel path. Strong lensing produces several images from the same binary coalescence and is forecasted to have a promising rate in ground-based…

General Relativity and Quantum Cosmology · Physics 2022-03-16 Justin Janquart , Otto A. Hannuksela , K. Haris , Chris Van Den Broeck

We introduce differentiable indirection -- a novel learned primitive that employs differentiable multi-scale lookup tables as an effective substitute for traditional compute and data operations across the graphics pipeline. We demonstrate…

Graphics · Computer Science 2023-11-21 Sayantan Datta , Carl Marshall , Derek Nowrouzezahrai , Zhao Dong , Zhengqin Li