English
Related papers

Related papers: Imaging extended single crystal lattice distortion…

200 papers

Coherent diffractive imaging (CDI), using both X-rays and electrons, has made extremely rapid progress over the past two decades. The associated reconstruction algorithms are typically iterative, and seeded with a crude first estimate. A…

Image and Video Processing · Electrical Eng. & Systems 2019-06-25 Konstantin M. Pavlov , Kaye S. Morgan , Vasily I. Punegov , David M. Paganin

Molecular and polymeric crystals show a wide range of functional properties that arise from the interplay between the atomic-scale structure of their constituent molecules and the organization of these molecules within the crystal lattice…

We propose a level-set-based semi-Lagrangian method on graded adaptive Cartesian grids to address the problem of surface reconstruction from point clouds. The goal is to obtain an implicit, high-quality representation of real shapes that…

Numerical Analysis · Mathematics 2026-03-26 Silvia Preda , Matteo Semplice

X-ray ptychography is one of the versatile techniques for nanometer resolution imaging. The magnitude of the diffraction patterns is recorded on a detector and the phase of the diffraction patterns is estimated using phase retrieval…

Image and Video Processing · Electrical Eng. & Systems 2021-05-21 Prasan Shedligeri , Florian Schiffers , Semih Barutcu , Pablo Ruiz , Aggelos K Katsaggelos , Oliver Cossairt

Image segmentation is an important median level vision topic. Accurate and efficient multiphase segmentation for images with intensity inhomogeneity is still a great challenge. We present a new two-stage multiphase segmentation method…

Optimization and Control · Mathematics 2020-09-15 Xueyan Guo , Yunhua Xue , Chunlin Wu

This paper addresses three-dimensional signal distortion and image reconstruction issues in x-ray Bragg coherent diffraction imaging (BCDI) in the event of a general non-orthogonal orientation of the area detector with respect to the…

Instrumentation and Detectors · Physics 2020-12-07 Siddharth Maddali , Marc Allain , Peng Li , Virginie Chamard , Stephan O. Hruszkewycz

Reflective ptychography is a promising lensless imaging technique with a wide field of view, offering significant potential for applications in semiconductor manufacturing and detection. However, many semiconductor materials are coated with…

Optics · Physics 2025-01-03 Yun Gao , Qijun You , Peixiang Lu , Wei Cao

The primal-dual hybrid gradient (PDHG) algorithm for solving convex optimization problems that arise in tomographic imaging is revisited. In particular, simplification of the selection of step-size parameters is developed for optimization…

Optimization and Control · Mathematics 2026-04-28 Emil Y. Sidky , John Paul Phillips , Zheng Zhang , Dan Xia , Ingrid S. Reiser , Xiaochuan Pan

We present a multiscale continuous Galerkin (MSCG) method for the fast and accurate stochastic simulation and optimization of time-harmonic wave propagation through photonic crystals. The MSCG method exploits repeated patterns in the…

Numerical Analysis · Mathematics 2020-04-30 Ferran Vidal-Codina , Joel Saa-Seoane , Ngoc-Cuong Nguyen , Jaime Peraire

We investigate an extended version of the Bragg reflection waveguide (BRW) with air gaps as one of the layers. This design has the potential of drastically simplifying the epitaxial structure for integrated nonlinear optical elements at the…

Optics · Physics 2015-06-17 Benedikt Pressl , Gregor Weihs

We present and analyse an approach to image reconstruction problems with imperfect forward models based on partially ordered spaces - Banach lattices. In this approach, errors in the data and in the forward models are described using order…

Numerical Analysis · Computer Science 2018-08-15 Yury Korolev , Jan Lellmann

Variational level set method has become a powerful tool in image segmentation due to its ability to handle complex topological changes and maintain continuity and smoothness in the process of evolution. However its evolution process can be…

Computer Vision and Pattern Recognition · Computer Science 2024-06-27 Fanghui Song , Jiebao Sun , Shengzhu Shi , Zhichang Guo , Dazhi Zhang

While the advances in synchrotron light sources, together with the development of focusing optics and detectors, allow nanoscale ptychographic imaging of materials and biological specimens, the corresponding experiments can yield…

Distributed, Parallel, and Cluster Computing · Computer Science 2022-04-05 Xiaodong Yu , Viktor Nikitin , Daniel J. Ching , Selin Aslan , Doga Gursoy , Tekin Bicer

This paper studies a recovery task of finding a low multilinear-rank tensor that fulfills some linear constraints in the general settings, which has many applications in computer vision and graphics. This problem is named as the low…

Optimization and Control · Mathematics 2013-10-08 Lei Yang , Zheng-Hai Huang , Yufan Li

We introduce an efficient and scalable method for density-based multi-material topology optimization, integrating classical mirror descent techniques with point-wise polytopal design constraints. Such constraints arise naturally in this…

Numerical Analysis · Mathematics 2026-05-15 Peter Gangl , Brendan Keith , Dohyun Kim , Boyan S. Lazarov , Thomas M. Surowiec

Speckle-based phase-contrast X-ray imaging (SB-PCXI) can reconstruct high-resolution images of weakly-attenuating materials that would otherwise be indistinguishable in conventional attenuation-based imaging. The experimental setup of…

Medical Physics · Physics 2023-07-31 Samantha J. Alloo , Kaye S. Morgan , David M. Paganin , Konstantin M. Pavlov

The well-known phase problem which means image reconstruction from only spectrum magnitude without using any spectrum phase information is considered basically in application to VLBI mapping of compact extragalactic radio sources (active…

Instrumentation and Methods for Astrophysics · Physics 2012-11-13 A. T. Bajkova

In ptychography experiments, redundant scanning is usually required to guarantee the stable recovery, such that a huge amount of frames are generated, and thus it poses a great demand of parallel computing in order to solve this large-scale…

Numerical Analysis · Mathematics 2021-02-05 Huibin Chang , Roland Glowinski , Stefano Marchesini , Xue-cheng Tai , Yang Wang , Tieyong Zeng

Analysis of distortions of the crystal lattice within individual mineral grains is central to the investigation of microscale processes that control and record tectonic events. These distortions are generally combinations of lattice…

Materials Science · Physics 2019-06-04 David Wallis , Lars N. Hansen , T. Ben Britton , Angus J. Wilkinson

Lattice defects play a key role in determining the properties of crystalline materials. Probing the 3D lattice strains that govern their interactions remains a challenge. Bragg Coherent Diffraction Imaging (BCDI) allows strain to be…