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Related papers: Ptychographic X-ray Speckle Tracking

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Label free tracking of small bio-particles such as proteins or viruses is of great utility in the study of biological processes, however such experiments are frequently hindered by weak signal strengths and a susceptibility to scattering…

Optics · Physics 2021-08-03 Joel Berk , Carl Paterson , Matthew R. Foreman

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

Optical imperfections, misalignments, aberrations, and even dust can significantly limit sensitivity in high-contrast imaging systems such as coronagraphs. An upstream deformable mirror (DM) in the pupil can be used to correct or compensate…

Instrumentation and Methods for Astrophysics · Physics 2015-06-15 Johanan L. Codona , Matthew Kenworthy

The development of robust, real-time optical methods for the detection and tracking of particles in complex multiple scattering media is a problem of practical importance in a number of fields, including environmental monitoring, air…

Optics · Physics 2025-02-04 Mohammadrasoul Taghavi , Edwin A. Marengo

Ptychography is a promising phase retrieval technique for label-free quantitative phase imaging. Recent advances in phase retrieval algorithms witnessed the development of spectral methods, in order to accelerate gradient descent…

Optics · Physics 2021-04-07 Lorenzo Valzania , Jonathan Dong , Sylvain Gigan

This work is concerned with optical imaging in strongly diffusive environments. We consider a typical setting in optical coherence tomography where a sample is probed by a collection of wavefields produced by a laser and propagating through…

Optics · Physics 2024-12-10 Randy Bartels , Olivier Pinaud , Maxine Varughese

One of the challenges in phase measuring deflectometry is to retrieve the wavefront from objects that present discontinuities or non-differentiable gradient fields. Here, we propose the integration of such gradients fields based on an…

Numerical Analysis · Mathematics 2023-06-02 Ricardo Legarda-Saenz , Jorge L. Flores , Manuel Servin , Anabel Martin-Gonzalez

High-contrast imaging from space must overcome two major noise sources to successfully detect a terrestrial planet angularly close to its parent star: photon noise from diffracted star light, and speckle noise from star light scattered by…

Astrophysics · Physics 2009-11-13 Pascal J. Borde , Wesley A. Traub

We develop a means for speckle-based phase imaging of the projected thickness of a single-material object, under the assumption of illumination by spatially random time-independent x-ray speckles. These speckles are generated by passing x…

We have performed coherent x-ray scattering experiments on the hexagonally reconstructed Pt (001) surface to study the temperature-dependent surface dynamics. By correlating speckle patterns collected at the (001) anti-Bragg position we are…

Materials Science · Physics 2011-09-26 M. S. Pierce , D. Hennessy , K. C. Chang , V. Komanicky , J. Strzalka , A. Sandy , A. Barbour , H. You

Metagratings have been shown to form an agile and efficient platform for extreme wavefront manipulation, going beyond the limitations of gradient metasurfaces. Previous approaches for transmissive metagratings have resorted on compound…

The structural complexity and instability of many interference phase microscopy methods are the major obstacles toward high-precision phase measurement. In this vein, improving more efficient configurations as well as proposing new methods…

Optics · Physics 2020-01-08 Samira Ebrahimi , Masoomeh Dashtdar

An interferometric fluorescent microscope and a novel theoretic image reconstruction approach were developed and used to obtain super-resolution images of live biological samples and to enable dynamic real time tracking. The tracking…

High-contrast imaging provided by a coronagraph is critical for the direction imaging of the Earth-like planet orbiting its bright parent star. A major limitation for such direct imaging is the speckle noise that is induced from the…

Instrumentation and Methods for Astrophysics · Physics 2015-10-14 JiangPei Dou , DeQing Ren , YongTian Zhu , Xi Zhang

Phase-sensitive coherent imaging exploits changes in the phases of backscattered light to observe tiny alterations of scattering structures or variations of the refractive index. But moving scatterers or a fluctuating refractive index…

X-ray fluorescence holography (XFH) is a method for obtaining diffraction-limited images of the local atomic structure around a given type of emitter. The reconstructed wave-field represents a distorted image of the scatterer electron…

Condensed Matter · Physics 2009-09-29 S. Marchesini , C. S. Fadley , F. J. Garcia de Abajo

Direct imaging of exoplanets requires very high contrast levels, which are obtained using coronagraphs. But residual quasi-static aberrations create speckles in the focal plane downstream of the coronagraph which mask the planet. This…

Instrumentation and Methods for Astrophysics · Physics 2015-06-16 J. Mazoyer , P. Baudoz , R. Galicher , M. Mas , G. Rousset

We examine the interplay between spectral bandwidth and illumination curvature in ptychography. By tailoring the divergence of the illumination, broader spectral bandwidths can be tolerated without requiring algorithmic modifications to the…

In astronomy and microscopy, distortions in the wavefront affect the dynamic range of a high contrast imaging system. These aberrations are either imposed by a turbulent medium such as the atmosphere, by static or thermal aberrations in the…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Benjamin Pope , Nick Cvetojevic , Anthony Cheetham , Frantz Martinache , Barnaby Norris , Peter Tuthill

We introduce wavefront shaping as a tool for optimizing the sensitivity in nano-optomechanical measurement schemes. We perform multimode output analysis of an optomechanical system consisting of a focused laser beam coupled to the…