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We consider an inverse source problem for partially coherent light propagating in the Fresnel regime. The data is the coherence of the field measured away from the source. The reconstruction is based on a minimum residue formulation, which…

A method for solving the inverse problem of designing the structure of a one-dimensional photonic crystal is proposed and experimentally implemented. It is known that a one-dimensional photonic crystal with a spatial sinusoidal modulation…

Optics · Physics 2023-08-09 P. S. Emelyantsev , N. I. Pyshkov , S. E. Svyakhovskiy

Curved refractive objects are common in the human environment, and have a complex visual appearance that can cause robotic vision algorithms to fail. Light-field cameras allow us to address this challenge by capturing the view-dependent…

Robotics · Computer Science 2021-04-20 Dorian Tsai , Peter Corke , Thierry Peynot , Donald G. Dansereau

We present a new method for estimating the Neural Reflectance Field (NReF) of an object from a set of posed multi-view images under unknown lighting. NReF represents 3D geometry and appearance of objects in a disentangled manner, and are…

Computer Vision and Pattern Recognition · Computer Science 2022-10-11 Xiu Li , Xiao Li , Yan Lu

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

We address the problem of recovering the shape and spatially-varying reflectance of an object from multi-view images (and their camera poses) of an object illuminated by one unknown lighting condition. This enables the rendering of novel…

Computer Vision and Pattern Recognition · Computer Science 2021-12-23 Xiuming Zhang , Pratul P. Srinivasan , Boyang Deng , Paul Debevec , William T. Freeman , Jonathan T. Barron

This paper concerns time-harmonic inverse source problems with a single far-field pattern in two dimensions, where the source term is compactly supported in an a priori given inhomogeneous background medium. For convex-polygonal source…

Analysis of PDEs · Mathematics 2020-03-13 Guanghui Hu , Jingzhi Li

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

To overcome the resolution limit of conventional optics, near field imaging techniques using a negative index flat lens (NIFL) have been previously developed that amplify the evanescent components of the incident field. Here, a technique is…

Optics · Physics 2016-12-23 Wyatt Adams , Durdu Ö. Güney

This paper addresses the problem of inverse rendering from photometric images. Existing approaches for this problem suffer from the effects of self-shadows, inter-reflections, and lack of constraints on the surface reflectance, leading to…

Computer Vision and Pattern Recognition · Computer Science 2025-04-09 Jingzhi Bao , Guanying Chen , Shuguang Cui

We present a focal surface projection to solve the narrow depth-of-field problem in projection mapping applications. We apply a phase-only spatial light modulator to realize nonuniform focusing distances, whereby the projected contents…

Optics · Physics 2023-09-06 Fumitaka Ueda , Yuta Kageyama , Daisuke Iwai , Kosuke Sato

We introduce a novel framework for solving inverse problems using NeRF-style generative models. We are interested in the problem of 3-D scene reconstruction given a single 2-D image and known camera parameters. We show that naively…

Computer Vision and Pattern Recognition · Computer Science 2021-12-17 Giannis Daras , Wen-Sheng Chu , Abhishek Kumar , Dmitry Lagun , Alexandros G. Dimakis

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

This paper continues the study of a class of compact convex hypersurfaces in Euclidean space $R^{n+1}, ~n \geq 1$, which are boundaries of compact convex bodies obtained by taking the intersection of (solid) confocal paraboloids of…

Differential Geometry · Mathematics 2007-05-23 Vladimir Oliker

In this article, we propose a new dimensionality-independent and gradient-free sampler, called Geometric Optics Approximation Sampling, which is based on the reflector antenna system. The core idea is to construct a reflecting surface that…

Numerical Analysis · Mathematics 2024-11-18 Zejun Sun , Guang-Hui Zheng

We show that radiation from complex and inherently random but correlated wave sources can be modelled efficiently by using an approach based on the Wigner distribution function. Our method exploits the connection between correlation…

Chaotic Dynamics · Physics 2015-09-30 Gabriele Gradoni , Stephen Creagh , Gregor Tanner , Christopher Smartt , David Thomas

Eliminating reflections caused by incident light interacting with reflective medium remains an ill-posed problem in the image restoration area. The primary challenge arises from the overlapping of reflection and transmission components in…

Computer Vision and Pattern Recognition · Computer Science 2025-09-17 Pengbo Guo , Chengxu Liu , Guoshuai Zhao , Xingsong Hou , Jialie Shen , Xueming Qian

Implicit representations like Neural Radiance Fields (NeRF) showed impressive results for photorealistic rendering of complex scenes with fine details. However, ideal or near-perfectly specular reflecting objects such as mirrors, which are…

Computer Vision and Pattern Recognition · Computer Science 2023-10-17 Leif Van Holland , Ruben Bliersbach , Jan U. Müller , Patrick Stotko , Reinhard Klein

The reflectance field of a face describes the reflectance properties responsible for complex lighting effects including diffuse, specular, inter-reflection and self shadowing. Most existing methods for estimating the face reflectance from a…

Computer Vision and Pattern Recognition · Computer Science 2020-08-25 Mallikarjun B R. , Ayush Tewari , Tae-Hyun Oh , Tim Weyrich , Bernd Bickel , Hans-Peter Seidel , Hanspeter Pfister , Wojciech Matusik , Mohamed Elgharib , Christian Theobalt

We present a scheme for remotely addressing single nano-objects by means of near-field optical microscopy that makes only use of one of the most fundamental properties of electromagnetic radiation: its polarization. A medium containing…

Optics · Physics 2007-05-23 M. Brun , A. Drezet , H. Mariette , J. C. Woehl , S. Huant