Results 31 to 40 of about 1,452 (172)
Low-dose phase retrieval of biological specimens using cryo-electron ptychography
Nature Communications, 2020 Cryo-electron microscopy is widely employed in structural biology and uses phase contrast imaging. Here, the authors employ electron ptychography, a quantitative phase retrieval method for high-contrast, low-dose phase imaging of cryo-state rotavirus and
Liqi Zhou +16 more
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Enhancement of Partially Coherent Diffractive Images Using Generative Adversarial Network
AI, 2022 We present a deep learning-based generative model for the enhancement of partially coherent diffractive images. In lensless coherent diffractive imaging, a highly coherent X-ray illumination is required to image an object at high resolution.
Jong Woo Kim +2 more
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Elementary signals in ptychography
Optics Express, 2015 Ptychographic imaging has gained popularity for its high resolving power and sensitivity as well as for its ability to map simultaneously the sample's complex-valued refractive index and the illumination. Yet, despite significant progress that allows for reliable practical implementation, some of the technique's fundamentals remain poorly understood ...
da Silva, Julio Cesar, Menzel, Andreas
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A Parameter Refinement Method for Ptychography Based on Deep Learning Concepts
Condensed Matter, 2021 X-ray ptychography is an advanced computational microscopy technique, which is delivering exceptionally detailed quantitative imaging of biological and nanotechnology specimens, which can be used for high-precision X-ray measurements.
Francesco Guzzi +4 more
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, 2022 Coherent illumination reflected by a remote target may be secondarily scattered by intermediate objects or materials. Here we show that phase retrieval on remotely observed images of such scattered fields enables imaging of the illuminated object at resolution proportional to $λR_s/A_s$, where $R_s$ is the range between the scatterer and the target and
Huang, Qian +4 more
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Blind ptychography: uniqueness and ambiguities [PDF]
Inverse Problems, 2020 Abstract Ptychography with an unknown mask and object is analyzed for general ptychographic measurement schemes that are strongly connected and possess an anchor. Under a mild constraint on the mask phase, it is proved that the masked object estimate must be the product of a block phase factor and the true masked ...
Albert Fannjiang, Pengwen Chen
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Continuous scanning mode for ptychography [PDF]
Optics Letters, 2014 We outline how ptychographic imaging can be performed without the need for discrete scan positions. Through an idealized experiment, we demonstrate how a discrete-position scan regime can be replaced with a continuously scanned one with suitable modification of the reconstruction scheme based on coherent modes.
Jesse N, Clark +3 more
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Differential phase contrast for quantitative imaging and spectro-microscopy at a nanoprobe beamline
Journal of Synchrotron Radiation, 2023 The interaction of a focused X-ray beam with a sample in a scanning probe experiment can provide a variety of information about the interaction volume. In many scanning probe experiments X-ray fluorescence (XRF) is supplemented with measurements of the ...
Paul D. Quinn +5 more
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Advanced Engineering Materials, EarlyView.Mass density governs the protective behavior of oxide layers on nuclear fuel cladding. Ptychographic X‐ray computed tomography measures zirconium oxide grown on Zircaloy‐4 under reactor and autoclave conditions, revealing nearly identical bulk densities of 5.1 ± 0.80 g cm−3.
Okan Yetik +9 more
wiley +1 more source