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A diffractive arrangement that allows imaging of an object without any intermediate or complementary element is presented. This optical system with only two diffraction gratings forms color images with white light.

Optics · Physics 2009-02-02 José J. Lunazzi , Noemi I. R. Rivera

Pseudoscopic (inverted depth) images that keep a continuous parallax were shown to be possible by use of a double diffraction process intermediated by a slit. One diffraction grating directing light to the slit acts as a wavelength encoder…

Optics · Physics 2009-11-13 Jose J. Lunazzi , Noemi I. Rivera

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

We present a differentiable framework to adaptively compute 4D illumination conditions with respect to an object, for efficient, high-quality simultaneous acquisition of its shape and reflectance, with a unified spatial-angular structured…

Computer Vision and Pattern Recognition · Computer Science 2026-05-08 Huakeng Ding , Yaowen Chen , Kun Zhou , Hongzhi Wu

We present total and specular reflectance measurements of various materials that are commonly (and uncommonly) used to provide baffling and/or to minimize the effect of stray light in optical systems. More specifically, we investigate the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Jennifer L. Marshall , Patrick Williams , Jean-Philippe Rheault , Travis Prochaska , Richard D. Allen , D. L. DePoy

We consider the problem of blind ptychography, that is the joint estimation of an unknown object and an illumination function from diffraction intensity measurements. In ptychography, diffraction measurements from neighboring regions of the…

Optimization and Control · Mathematics 2016-02-04 Stefano Marchesini , Hau-Tieng Wu

Active illumination is a prominent complement to enhance 2D face recognition and make it more robust, e.g., to spoofing attacks and low-light conditions. In the present work we show that it is possible to adopt active illumination to…

Computer Vision and Pattern Recognition · Computer Science 2020-04-08 J. Matias Di Martino , Fernando Suzacq , Mauricio Delbracio , Qiang Qiu , Guillermo Sapiro

Learning neural radiance fields of a scene has recently allowed realistic novel view synthesis of the scene, but they are limited to synthesize images under the original fixed lighting condition. Therefore, they are not flexible for the…

Computer Vision and Pattern Recognition · Computer Science 2021-10-26 Quan Zheng , Gurprit Singh , Hans-Peter Seidel

A white light system based on a 65 cm x 35 cm diffractive screen is demonstrated to be capable of displaying three-dimensional figures with continuous horizontal parallax. Three computer-controlled mirrors and a diffractive-refractive…

Optics · Physics 2015-05-27 Jose J. Lunazzi , M. Diamand

We introduce a high resolution spatially adaptive light source, or a projector, into a neural reflectance field that allows to both calibrate the projector and photo realistic light editing. The projected texture is fully differentiable…

Computer Vision and Pattern Recognition · Computer Science 2023-06-13 Yotam Erel , Daisuke Iwai , Amit H. Bermano

The precise determination of the instrumental response function versus wavelength is a central ingredient in contemporary photometric calibration strategies. This typically entails propagating narrowband illumination through the system…

Hyperspectral 3D imaging aims to acquire both depth and spectral information of a scene. However, existing methods are either prohibitively expensive and bulky or compromise on spectral and depth accuracy. In this work, we present Dispersed…

Image and Video Processing · Electrical Eng. & Systems 2024-03-26 Suhyun Shin , Seokjun Choi , Felix Heide , Seung-Hwan Baek

The spectral dispersion of light is critical in applications ranging from spectroscopy to sensing and optical communication technologies. We demonstrate that ultra-high spectral dispersion can be achieved with a finite-size surface plasmon…

Strongly Correlated Electrons · Physics 2007-05-23 V. Mikhailov , J. Elliott , G. Wurtz , P. Bayvel , A. V. Zayats

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…

We study strong gravitational lensing in a static, spherically symmetric, naked singularity spacetime, without a photon sphere. The nature of the singularity is found to be lightlike. We discuss the characteristic lensing features of this…

General Relativity and Quantum Cosmology · Physics 2020-09-25 Suvankar Paul

Free-space light beams with complex intensity patterns, or non-trivial phase structure, are demanded in diverse fields, ranging from classical and quantum optical communications, to manipulation and imaging of microparticles and cells.…

Optics · Physics 2016-12-13 Andrea Crespi , Francesca Bragheri

Motivated by their great potential to reduce the size, cost and weight, flat lenses, a category that includes diffractive lenses and metalenses, are rapidly emerging as key components with the potential to replace the traditional refractive…

Optics · Physics 2023-08-25 Roy Maman , Eitan Mualem , Noa Mazurski , Jacob Engelberg , Uriel Levy

A method for displaying volumetric images, which exploits our binocular vision and does not require eyewear, is discussed. The display can be rendered as a matrix of pivoting micromirrors irradiated by a light beam; each micromirror focuses…

Optics · Physics 2007-07-04 Oleg G. Semyonov

Pseudoscopic images that keep the continuous parallax are shown to be possible due to a double diffraction process intermediated by a slit. One diffraction grating acts as a wavelength encoder of views while a second diffraction grating…

Optics · Physics 2015-06-26 Jose J. Lunazzi , Noemi I. Rivera

The relationship between transmission area of an object imaged and the visibility of its image is investigated in a lensless system. We show that the changes of the visibility are quite different when the transmission area is varied by…

Quantum Physics · Physics 2009-11-13 Yanfeng Bai , Shensheng Han , Honglin Liu