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The increasing use of freeform optical surfaces raises the demand for optical design tools developed for generalized systems. In the design process surface-by-surface aberration contributions are of special interest. The expansion of the…

Optics · Physics 2025-12-02 Mateusz Oleszko , Ralf Hambach , Herbert Gross

In this article, we present a general mode-conversion algorithm allowing to build an optical system composed of an alternation of phase masks and free propagations. The originality of our approach lies in the introduction of free parameters…

Computational Physics · Physics 2020-06-08 Nicolas Barré

Intelligent reflecting surface (IRS) is a cost-efficient technique to improve power efficiency and spectral efficiency. However, IRS-aided multi-antenna transmission needs to jointly optimize the passive and active beamforming, imposing a…

Information Theory · Computer Science 2022-05-03 Wei Jiang , Hans Dieter Schotten

In the conventional approach to lens imaging, rays are used to map object points to image points. However, many students have a need to think of the image as a whole. To answer this need, lens imaging is reinterpreted as a superposition of…

Physics Education · Physics 2016-01-20 Sascha Grusche

This paper addresses the problem of image matting for transparent objects. Existing approaches often require tedious capturing procedures and long processing time, which limit their practical use. In this paper, we formulate transparent…

Computer Vision and Pattern Recognition · Computer Science 2019-07-29 Guanying Chen , Kai Han , Kwan-Yee K. Wong

Optics related to non-Euclidean geometry has been attracting growing interest for emerged novel phenomena and the analog for general relativity, while most studies are limited to the free space on rotationally-symmetric surfaces. In this…

Recognized for their non-diffracting properties, Bessel beams can be conveniently combined to generate the so-called Frozen Waves, which are monochromatic beams endowed with topological charge and whose longitudinal intensity pattern can be…

Reflective imaging systems form an important part of photonic devices such as spectrometers, telescopes, augmented and virtual reality headsets or lithography platforms. Reflective optics provide unparalleled spectral performance and can be…

We propose an inverse method to design two-dimensional freeform imaging systems. We present the mathematical model to design a parallel-to-point double-reflector imaging system using inverse methods from nonimaging optics. We impose an…

A novel concept for dynamic focus shaping based on highly efficient coherent beam combining with microlens arrays (MLA) as combining element is presented. This concept allows to control the power weights of diffraction orders by varying the…

Recovering the 3D shape of transparent objects using a small number of unconstrained natural images is an ill-posed problem. Complex light paths induced by refraction and reflection have prevented both traditional and deep multiview stereo…

Computer Vision and Pattern Recognition · Computer Science 2020-07-24 Zhengqin Li , Yu-Ying Yeh , Manmohan Chandraker

We consider the design of polyphase waveforms for ground moving target detection with airborne multiple-input-multiple-output (MIMO) radar. Due to the constant-modulus and finite-alphabet constraint on the waveforms, the associated design…

Signal Processing · Electrical Eng. & Systems 2020-10-28 Bo Tang , Jonathan Tuck , Peter Stoica

Unidirectional optical systems enable selective control of light through asymmetric processing of radiation, effectively transmitting light in one direction while blocking unwanted propagation in the opposite direction. Here, we introduce a…

Optics · Physics 2025-03-21 Yuhang Li , Tianyi Gan , Jingxi Li , Mona Jarrahi , Aydogan Ozcan

Aberrations limit scanning fluorescence microscopy when imaging in scattering materials such as biological tissue. Model-based approaches for adaptive optics take advantage of a computational model of the optical setup. Such models can be…

Optics · Physics 2021-07-07 Ivan Vishniakou , Johannes D. Seelig

In this paper, we present a new robotic system to perform defect inspection tasks over free-form specular surfaces. The autonomous procedure is achieved by a six-DOF manipulator, equipped with a line scan camera and a high-intensity…

Robotics · Computer Science 2020-08-26 Shengzeng Huo , David Navarro-Alarcon , David Chik

The aim of this research is to reconstruct the 3D X-ray refractive index gradient maps by the proposed vector Radon transform and its inverse, assuming that the small-angle deviation condition is met. Theoretical analyses show that the…

Medical Physics · Physics 2023-09-20 Keliang Liao , Qili He , Panyun Li , Liang Luo , Peiping Zhu

Recently, differentiable volume rendering in neural radiance fields (NeRF) has gained a lot of popularity, and its variants have attained many impressive results. However, existing methods usually assume the scene is a homogeneous volume so…

Computer Vision and Pattern Recognition · Computer Science 2022-11-29 Jen-I Pan , Jheng-Wei Su , Kai-Wen Hsiao , Ting-Yu Yen , Hung-Kuo Chu

Multiple lidars are prevalently used on mobile vehicles for rendering a broad view to enhance the performance of localization and perception systems. However, precise calibration of multiple lidars is challenging since the feature…

Computer Vision and Pattern Recognition · Computer Science 2019-04-30 Jianhao Jiao , Qinghai Liao , Yilong Zhu , Tianyu Liu , Yang Yu , Rui Fan , Lujia Wang , Ming Liu

Refractive Index Tomography is the inverse problem of reconstructing the continuously-varying 3D refractive index in a scene using 2D projected image measurements. Although a purely refractive field is not directly visible, it bends light…

Computer Vision and Pattern Recognition · Computer Science 2023-12-06 Brandon Zhao , Aviad Levis , Liam Connor , Pratul P. Srinivasan , Katherine L. Bouman

In this paper, we present a new framework for reducing the computational complexity of geometric vision problems through targeted reweighting of the cost functions used to minimize reprojection errors. Triangulation - the task of estimating…

Computer Vision and Pattern Recognition · Computer Science 2025-03-12 Felix Rydell , Georg Bökman , Fredrik Kahl , Kathlén Kohn
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