English
Related papers

Related papers: Coherent imaging of extended objects

200 papers

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

We explore the oscillatory behavior observed in inversion methods applied to large-scale text-to-image diffusion models, with a focus on the "Flux" model. By employing a fixed-point-inspired iterative approach to invert real-world images,…

Computer Vision and Pattern Recognition · Computer Science 2024-11-19 Yan Zheng , Zhenxiao Liang , Xiaoyan Cong , Lanqing guo , Yuehao Wang , Peihao Wang , Zhangyang Wang

Object detection and semantic segmentation are two of the most widely adopted deep learning algorithms in agricultural applications. One of the major sources of variability in image quality acquired in the outdoors for such tasks is…

Computer Vision and Pattern Recognition · Computer Science 2022-03-29 Abhisesh Silwal , Tanvir Parhar , Francisco Yandun , George Kantor

Recent advances in the field of attosecond science hold the promise of tracking electronic processes at the shortest space and time scales. Imaging methods that combine attosecond temporal with nanometer spatial resolution are currently out…

We consider the non-line-of-sight (NLOS) imaging of an object using the light reflected off a diffusive wall. The wall scatters incident light such that a lens is no longer useful to form an image. Instead, we exploit the 4D spatial…

Computer Vision and Pattern Recognition · Computer Science 2022-12-06 Andre Beckus , Alexandru Tamasan , George K. Atia

Holography is an established technique for measuring the wavefront of optical signals through interferometric combination with a reference wave. Conventionally the integration time of a hologram is limited by the interferometer coherence…

Optics · Physics 2023-12-13 Guillaume Thekkadath , Duncan England , Benjamin Sussman

In disordered materials under mechanical stress, the produced deformation can deviate from the affine one already in the elastic regime. The nonaffine contribution was observed and characterized in numerical simulations for various systems.…

Soft Condensed Matter · Physics 2021-12-17 Alesya Mikhailovskaya , Julien Fade , Jérôme Crassous

Aberrations limit optical systems in many situations, for example when imaging in biological tissue. Machine learning offers novel ways to improve imaging under such conditions by learning inverse models of aberrations. Learning requires…

Optics · Physics 2021-04-30 Ivan Vishniakou , Johannes D. Seelig

(abridged) Imaging observations are generally affected by a fluctuating background of speckles, a particular problem when detecting faint stellar companions at small angular separations. Knowing the distribution of the speckle intensities…

Astrophysics · Physics 2009-11-13 Michael P. Fitzgerald , James R. Graham

In this paper we analyze the image formation problem for undulator radiation through an optical system, accounting for the influence of the electron beam emittance. On the one hand, image formation with Synchrotron Radiation is governed by…

Accelerator Physics · Physics 2009-09-29 Gianluca Geloni , Evgeni Saldin , Evgeni Schneidmiller , Mikhail Yurkov

Coherent X-ray diffraction microscopy is a method of imaging non-periodic isolated objects at resolutions only limited, in principle, by the largest scattering angles recorded. We demonstrate X-ray diffraction imaging with high resolution…

Recent realization of Bose-Einstein condensation of light in 2D provides a new platform for studying novel phases and phase transitions. The combination of low effective mass of the confined light and the presence of the dye molecules with…

Quantum Gases · Physics 2019-04-30 Victor Fleurov , Anatoly Kuklov

In both light optics and electron optics, the amplitude of a wave scattered by an object is an observable that is usually recorded in the form of an intensity distribution in a real space image or a diffraction image. In contrast, retrieval…

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

Electronic energy transfer in photosynthesis occurs over a range of time scales and under a variety of intermolecular coupling conditions. Recent work has shown that electronic coupling between chromophores can lead to coherent oscillations…

Ptychography is a lensless, computational imaging method that utilises diffraction patterns to determine the amplitude and phase of an object. In transmission ptychography, the diffraction patterns are recorded by a detector positioned…

Image and Video Processing · Electrical Eng. & Systems 2023-01-04 Kira A. M. Maathuis , Jacob Seifert , Allard P. Mosk

Propagation of light through media with a complex refractive index in which gain and loss are engineered to be $PT$ symmetric has many remarkable features. In particular the usual unitarity relations are not satisfied, so that the…

Optics · Physics 2015-06-03 H. F. Jones

Novel optical phenomena, including electromagnetically induced transparency, slow light, superluminal light propagation, have recently been demonstrated in diverse physical implementations. These phenomena are challenging to realize in…

Optics · Physics 2007-12-03 Vikas Anant , Ayman F. Abouraddy , Karl K. Berggren

Complex-field imaging is indispensable for numerous applications at wavelengths from X-ray to THz, with amplitude describing transmittance (or reflectivity) and phase revealing intrinsic structure of the target object. Coherent diffraction…

Image and Video Processing · Electrical Eng. & Systems 2021-04-07 Meng Li , Liheng Bian , Guoan Zheng , Andrew Maiden , Yang Liu , Yiming Li , Qionghai Dai , Jun Zhang

With the present and soon-to-be breakthrough of optical interferometry, countless objects shall be within reach of interferometers; yet, most of them are expected to remain only marginally resolved with hectometric baselines. In this paper,…

Astrophysics · Physics 2009-11-07 Regis Lachaume