English
Related papers

Related papers: Optimization based evaluation of grating interfero…

200 papers

Phase-wrapping artifacts, statistical image noise and the need for a minimum amount of phase steps per projection limit the practicability of x-ray grating based phase-contrast tomography, when using filtered back projection reconstruction.…

Wavefront sensing involves estimating the phase and intensity of light, enabling a wide range of imaging applications, from adaptive optics and astronomy to biomedical imaging. Since conventional image sensors can only measure the spatial…

Image and Video Processing · Electrical Eng. & Systems 2026-04-07 Nebiyou Yismaw , Vishwanath Saragadam , Aswin C. Sankaranarayanan , M. Salman Asif

Complex object wave recovery from single-shot interference pattern is an important practical problem in interferometry and digital holography. The most popular single-shot interferogram analysis method involves Fourier filtering of…

Image and Video Processing · Electrical Eng. & Systems 2019-06-28 Sunaina , Mansi Butola , Kedar Khare

We study the capabilities of time-modulated diffraction gratings as imaging devices. It is shown that a time-dependent but transversally homogeneous slab can be used to make a perfect image of an object in the far-field, since all the…

Optics · Physics 2022-04-05 Pawel Packo , Dani Torrent

Fast characterization of 2-dimensional gratings is demonstrated using a Fourier lens optical system and a differential optimization algorithm. It is shown that both the grating specific parameters such as the basis vectors and the angle…

Instrumentation and Detectors · Physics 2016-01-15 Morten Hannibal Madsen , Pierre Boher , Poul-Erik Hansen , Jan Friis Jørgensen

In X-ray phase contrast imaging, phase retrieval from intensity measurements is the key for further quantitative analysis and tomographic reconstructions. In this letter, we present a single-shot approach for quantitative phase retrieval in…

Instrumentation and Detectors · Physics 2016-10-03 Wang Zhili , Liu Dalin

Fourier-based modal methods are among the most effective numerical tools for the accurate analysis of crossed gratings. However, leading to computationally expensive eigenvalue equations significantly restricts their applicability,…

Optics · Physics 2021-06-08 Ehsan Faghihifar , Mahmood Akbari , Seyed Amir Hossein Nekuee

The displacement field in highly non uniformly strained crystals is obtained by addition of constraints to an iterative phase retrieval algorithm. These constraints include direct space density uniformity and also constraints to the sign…

Materials Science · Physics 2009-11-11 A. A. Minkevich , M. Gailhanou , J. -S. Micha , B. Charlet , V. Chamard , O. Thomas

Large-area gratings play a crucial role in various engineering fields. However, traditional interference lithography is limited by the size of optical component apertures, making large-area fabrication a challenging task. Here, a method for…

Optics · Physics 2024-11-05 Xiang Gao , Jingwen Li , Zijian Zhong , Xinghui Li

Many iterative procedures in stochastic optimization exhibit a transient phase followed by a stationary phase. During the transient phase the procedure converges towards a region of interest, and during the stationary phase the procedure…

Machine Learning · Statistics 2018-02-26 Jerry Chee , Panos Toulis

Pose graph optimization is a special case of the simultaneous localization and mapping problem where the only variables to be estimated are pose variables and the only measurements are inter-pose constraints. The vast majority of pose graph…

Robotics · Computer Science 2022-12-09 Brendon Forsgren , Kevin Brink , Prashant Ganesh , Timothy McLain

Purpose: Field monitoring measures field perturbations, which can be accounted for during image reconstructions. In certain field monitoring environments, significant phase deviations can arise far from isocenter due to the finite extent of…

Medical Physics · Physics 2023-01-25 Paul I. Dubovan , Kyle M. Gilbert , Corey A. Baron

A novel approach for measuring linear X-ray polarization over a broad-band using conventional imaging optics and cameras is described. A new type of high efficiency grating, called the critical angle transmission grating is used to disperse…

Astrophysics · Physics 2009-11-13 Herman L. Marshall

Interlaced Spin Grating is a scheme for the preparation of spectro-spatial periodic absorption gratings in a inhomogeneously broadened absorption profile. It relies on the optical pumping of atoms in a nearby long-lived ground state…

In this paper we compare the performance of multi and single-mode interferometry for the estimation of the phase of the complex visibility. We provide a theoretical description of the interferometric signal which enables to derive the phase…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 E. Tatulli , N. Blind , J. P. Berger , A. Chelli , F. Malbet

Fabrication of X-ray gratings has surged in the last two decades thanks to their vast employment in X-ray Phase Contrast Imaging, an imaging technique able to boost X-ray sensitivity to detect otherwise invisible details. These high aspect…

Fourier ptychography (FP), as a computational imaging method, is a powerful tool to improve imaging resolution. Camera-scanning Fourier ptychography extends the application of FP from micro to macro creatively. Due to the non-ideal scanning…

Image and Video Processing · Electrical Eng. & Systems 2022-06-08 Baiqi Cui , Shaohui Zhang , Yechao Wang , Yao Hu , Qun Hao

Phase-contrast and dark-field imaging are relatively new X-ray imaging modalities that provide additional information to conventional attenuation-based imaging. However, this new information comes at the price of a more complex acquisition…

In coherent X-ray diffraction microscopy the diffraction pattern generated by a sample illuminated with coherent x-rays is recorded, and a computer algorithm recovers the unmeasured phases to synthesize an image. By avoiding the use of a…

Rotations play a detrimental role in achieving ultra-high-performance inertial measurements with an atom interferometer, leading potentially to a total loss of interference contrast and the emergence of dominant phase shift biases. This…