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Related papers: Aberrated dark-field imaging systems

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Here the role and influence of aberrations in optical imaging systems employing partially coherent complex scalar fields is studied. Imaging systems require aberrations to yield contrast in the output image. For linear shift-invariant…

Optics · Physics 2015-06-30 Mario A. Beltran , Marcus J. Kitchen , T. Petersen , David M. Paganin

An optical imaging system forms an object image by recollecting light scattered by the object. However, intact optical information of the object delivered through the imaging system is deteriorated by imperfect optical elements and unwanted…

Optics · Physics 2017-03-28 SangYun Lee , Kyeoreh Lee , Seungwoo Shin , YongKeun Park

Diffraction tomography is an inverse scattering technique used to reconstruct the spatial distribution of the material properties of a weakly scattering object. The object is exposed to radiation, typically light or ultrasound, and the…

Numerical Analysis · Mathematics 2024-03-26 Clemens Kirisits , Noemi Naujoks , Otmar Scherzer

The presence of a scattering medium in the imaging path between an object and an observer is known to severely limit the visual acuity of the imaging system. We present an approach to circumvent the deleterious effects of scattering, by…

When light is passed through aberrated optical systems, the resulting degradation in amplitude and phase has deleterious effects, for example, on resolution in imaging, spot sizes in focussing, and the beam quality factor of the output…

Optics · Physics 2022-01-19 Wagner Tavares Buono , Jacuqueline Tau , Isaac Nape , Andrew Forbes

We consider the propagation of both fully coherent and partially coherent complex scalar fields, through linear shift-invariant imaging systems. The state of such imaging systems is characterized by a countable infinity of aberration…

Optics · Physics 2018-02-28 David M. Paganin , Timothy C. Petersen , Mario A. Beltran

We introduce a new notion for the deformation of Gabor systems. Such deformations are in general nonlinear and, in particular, include the standard jitter error and linear deformations of phase space. With this new notion we prove a strong…

Functional Analysis · Mathematics 2016-08-08 Karlheinz Gröchenig , Joaquim Ortega-Cerdà , José Luis Romero

The inversion of a diffraction pattern offers aberration-free diffraction-limited 3D images without the resolution and depth-of-field limitations of lens-based tomographic systems, the only limitation being radiation damage. We review our…

Focusing waves inside inhomogeneous media is a fundamental problem for imaging. Spatial variations of wave velocity can strongly distort propagating wavefronts and degrade image quality. Adaptive focusing can compensate for such aberration,…

Image and Video Processing · Electrical Eng. & Systems 2020-06-15 William Lambert , Laura A. Cobus , Thomas Frappart , Mathias Fink , Alexandre Aubry

Dark-field images are formed by small-angle scattering of x-ray photons. The small-angle scattering signal is particularly sensitive to structural variations and density fluctuation on a length scale of several ten to hundred nanometers,…

Medical Physics · Physics 2010-03-11 W. Cong , F. Pfeiffer , M. Bech , O. Bunk , C. David , G. Wang

Optical aberrations of optical systems cause significant degradation of imaging quality. Aberration correction by sophisticated lens designs and special glass materials generally incurs high cost of manufacturing and the increase in the…

Computer Vision and Pattern Recognition · Computer Science 2023-04-13 Shuang Cui , Bingnan Wang , Quan Zheng

The phasor field has been shown to be a valuable tool for non-line-of-sight imaging. We present a formal analysis of phasor-field imaging using paraxial wave optics. Then, we derive a set of propagation primitives---using the two-frequency,…

Optics · Physics 2019-07-24 Justin Dove , Jeffrey H. Shapiro

Dark-field X-ray imaging is a novel modality which visualises scattering from unresolved microstructure. Most dark-field imaging techniques rely on crystals or structured illumination, but recent work has shown that dark-field effects are…

Medical Physics · Physics 2024-09-04 Jannis N. Ahlers , Konstantin M. Pavlov , Marcus J. Kitchen , Kaye S. Morgan

When used with coherent light, optical imaging systems, even diffraction-limited, are inherently unable to reproduce both the amplitude and the phase of a two-dimensional field distribution because their impulse response function varies…

Optics · Physics 2009-11-13 E. Brainis , C. Muldoon , L. Brandt , A. Kuhn

Casual photography is often performed in uncontrolled lighting that can result in low quality images and degrade the performance of downstream processing. We consider the problem of estimating surface normal and reflectance maps of scenes…

Computer Vision and Pattern Recognition · Computer Science 2020-12-14 Zhihao Xia , Jason Lawrence , Supreeth Achar

Directional dark-field imaging is an emerging x-ray modality that is sensitive to unresolved anisotropic scattering from sub-pixel sample microstructures. A single-grid imaging set-up can be used to capture dark-field images by looking at…

Image and Video Processing · Electrical Eng. & Systems 2023-04-07 Michelle K Croughan , Ying Ying How , Allan Pennings , Kaye S Morgan

Motivated by their great potential to reduce the size, cost and weight, flat lenses, a category that includes diffractive lenses and metalenses, are rapidly emerging as key components with the potential to replace the traditional refractive…

Optics · Physics 2023-08-25 Roy Maman , Eitan Mualem , Noa Mazurski , Jacob Engelberg , Uriel Levy

We study the problem of deblurring light fields of general 3D scenes captured under 3D camera motion and present both theoretical and practical contributions. By analyzing the motion-blurred light field in the primal and Fourier domains, we…

Computer Vision and Pattern Recognition · Computer Science 2017-04-19 Pratul P. Srinivasan , Ren Ng , Ravi Ramamoorthi

We propose and numerically demonstrate a technique for subwavelength imaging based on a metal-dielectric multilayer hyperlens designed in such a way that only the large-wavevector waves are transmitted while all propagating waves from the…

Optics · Physics 2015-10-28 Taavi Repän , Andrei V. Lavrinenko , Sergei V. Zhukovsky

It is well known that by modifying the wavefront in a certain manner, the light intensity can be turned into a certain shape. However, all known light modulation techniques allow for limited light modifications only: focusing within a…

Optics · Physics 2016-05-23 Tatiana Latychevskaia , Hans-Werner Fink
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