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Related papers: Sampling requirements in near-field ptychography

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Graph-based transforms have been shown to be powerful tools in terms of image energy compaction. However, when the support increases to best capture signal dependencies, the computation of the basis functions becomes rapidly untractable.…

Computer Vision and Pattern Recognition · Computer Science 2020-02-19 Mira Rizkallah , Thomas Maugey , Christine Guillemot

Labelfree nanoscopy encompasses optical imaging with resolution in the 100 nm range using visible wavelengths. Here, we present a labelfree nanoscopy method that combines Fourier ptychography with waveguide microscopy to realize a…

Nonuniform Fourier data are routinely collected in applications such as magnetic resonance imaging, synthetic aperture radar, and synthetic imaging in radio astronomy. To acquire a fast reconstruction that does not require an online inverse…

Numerical Analysis · Mathematics 2016-10-05 Anne Gelb , Guohui Song

We demonstrate a technique that allows highly surface sensitive imaging of nanostructures on planar surfaces over large areas, providing a new avenue for research in materials science, especially for \textit{in situ} applications. The…

Accurate calibration of internal parameters is a crucial yet challenging prerequisite for 3D reconstruction using light field cameras. In this paper, we propose a linear fractional transformation(LFT) parameter $\alpha$ to decoupled the…

Computer Vision and Pattern Recognition · Computer Science 2025-11-07 Zhong Chen , Changfeng Chen

A novel phase retrieval method, motivated by ptychographic imaging, is proposed for the approximate recovery of a compactly supported specimen function $f:\mathbb{R}\rightarrow\mathbb{C}$ from its continuous short time Fourier transform…

Numerical Analysis · Mathematics 2017-06-07 Sami Merhi , Aditya Viswanathan , Mark Iwen

Fourier-transform spectroscopy (FTS) has been widely used as a standard analytical technique over the past half-century. FTS is a simple and robust autocorrelation-based technique that is compatible with both temporally coherent and…

Instrumentation and Detectors · Physics 2018-11-21 Kazuki Hashimoto , Takuro Ideguchi

Dark-field X-ray microscopy is a new full-field imaging technique that nondestructively maps the structure and local strain inside deeply embedded crystalline elements in three dimensions. Placing an objective lens in the diffracted beam…

Materials Science · Physics 2022-03-10 H. F. Poulsen , L. E. Dresselhaus-Marais , M. A. Carlsen , C. Detlefs , G. Winther

Optical photothermal microscopy is a powerful, emerging method that overcomes the diffraction limit in infrared hyperspectral imaging by utilizing a visible probe laser beam to detect local temperature-induced modulation at the visible…

Inverse scattering is the process of estimating the spatial distribution of the scattering potential of an object by measuring the scattered wavefields around it. In this paper, we consider reflection tomography of high contrast objects…

Signal Processing · Electrical Eng. & Systems 2020-12-17 Ajinkya Kadu , Hassan Mansour , Petros T. Boufounos

Sonography techniques use multiple transducer elements for tissue visualization. Signals detected at each element are sampled prior to digital beamforming. The required sampling rates are up to 4 times the Nyquist rate of the signal and…

Information Theory · Computer Science 2012-12-21 T. Chernyakova , Y. C. Eldar , R. Amit

Topo-Tomography (TT) is a synchrotron-based X-ray diffraction imaging technique used to characterize grain shape and crystal orientation in polycrystalline samples. This work aims to provide a decisive and fundamental understanding of 3D…

Computational Physics · Physics 2025-10-13 Zheheng Liu , Nicola Vigano , Henry Proudhon , Wolfgang Ludwig

Linear-dichroism is an important tool to characterize the transmission matrix and determine the crystal or orbital orientation in a material. In order to gain high resolution mapping of the transmission properties of such materials, we…

Optics · Physics 2020-02-12 Huibin Chang , Matthew A Marcus , Stefano Marchesini

Non-line-of-Sight (NLOS) imaging systems collect light at a diffuse relay surface and input this measurement into computational algorithms that output a 3D volumetric reconstruction. These algorithms utilize the Fast Fourier Transform (FFT)…

Image and Video Processing · Electrical Eng. & Systems 2025-01-14 Talha Sultan , Alex Bocchieri , Chaoying Gu , Xiaochun Liu , Pavel Polynkin , Andreas Velten

An approach reported recently by Alexandrov et al. on optical scatter imaging, termed digital Fourier microscopy (DFM), represents an adaptation of digital Fourier holography to selective imaging of biological matter. Holographic mode of…

Optics · Physics 2007-05-23 K. Y. T. Seet , P. Blazkiewicz , P. Meredith , A. V. Zvyagin

Low-light optical imaging refers to the use of cameras to capture images with minimal photon flux. This area has broad application to diverse fields, including optical microscopy for biological studies. In such studies, it is important to…

t is a known fact that near field diffraction or Fresnel diffraction calculations are difficult to perform exactly. It is in general necessary to make some approximations in order to obtain a more suitable form. In this work, a numerical…

Single-shot fluorescence imaging techniques have gained increasing interest in recent years due to their ability to rapidly capture complex biological data without the need for extensive scanning. In this letter, we introduce polarized…

Optics · Physics 2025-01-31 Oumeng Zhang , Changhuei Yang

Future optical interferometric instrumentation mainly relies on the availability of an efficient cophasing system: once available, what has so far postponed the relevance of direct imaging with an interferometer will vanish. This paper…

Astrophysics · Physics 2008-11-26 O. Lardiere , F. Martinache , F. Patru

Ptychography is now integrated as a tool in mainstream microscopy allowing quantitative and high-resolution imaging capabilities over a wide field of view. However, its ultimate performance is inevitably limited by the available coherent…

Computational Physics · Physics 2024-06-12 Wenhui Xu , Shoucong Ning , Pengju Sheng , Huixiang Lin , Angus I Kirkland , Yong Peng , Fucai Zhang