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Related papers: Focal-plane wavefront sensing with high-order adap…

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The correction of quasi-static wavefront errors within a coronagraphic optical system will be a key challenge to overcome in order to directly image exoplanets in reflected light. These quasi-static errors are caused by mid to high-order…

Instrumentation and Methods for Astrophysics · Physics 2024-06-28 Kian Milani , Ewan Douglas , Leonid Pogorelyuk , Christopher Mendillo , Kerri Cahoy , Nicholas Belsten , Brandon Eickert , Shanti Rao

Multifocal plane microscopy (MUM) allows three dimensional objects to be imaged in a single camera frame. Our approach uses dual orthogonal diffraction phase gratings with a quadratic distortion of the lines to apply defocus to the first…

Optics · Physics 2020-03-13 Benjamin Gore , Noah Schwartz , Paul Dalgarno

The motion of planar ground vehicles is often non-holonomic, and as a result may be modelled by the 2 DoF Ackermann steering model. We analyse the feasibility of estimating such motion with a downward facing camera that exerts…

Robotics · Computer Science 2022-03-02 Ling Gao , Junyan Su , Jiadi Cui , Xiangchen Zeng , Xin Peng , Laurent Kneip

Fourier ptychographic microscopy enables gigapixel-scale imaging, with both large field-of-view and high resolution. Using a set of low-resolution images that are recorded under varying illumination angles, the goal is to computationally…

Signal Processing · Electrical Eng. & Systems 2018-03-13 Emrah Bostan , Mahdi Soltanolkotabi , David Ren , Laura Waller

Improvements in X-ray optics critically depend on the measurement of their optical performance. The knowledge of wavefront aberrations, for example, can be used to improve the fabrication of optical elements or to design phase correctors to…

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…

Imaging faint objects, such as exoplanets or disks, around nearby stars is extremely challenging because host star images are dominated by the telescope diffraction pattern. Using a coronagraph is an efficient solution for removing…

High contrast imaging and spectroscopy provide unique constraints for exoplanet formation models as well as for planetary atmosphere models. But this can be challenging because of the planet-to-star small angular separation and high flux…

Instrumentation and Methods for Astrophysics · Physics 2016-04-06 J. -R. Delorme , R. Galicher , P. Baudoz , G. Rousset , J. Mazoyer , O. Dupuis

X-ray imaging is a fundamental tool of routine clinical diagnosis. Fluoroscopic imaging can further acquire X-ray images at video frame rates, thus enabling non-invasive in-vivo motion studies of joints, gastrointestinal tract, etc. For…

Image and Video Processing · Electrical Eng. & Systems 2018-10-22 Jacky C. K. Chow , Derek Lichti , Kathleen Ang , Gregor Kuntze , Gulshan Sharma , Janet Ronsky

The success of ground-based, high contrast imaging for the detection of exoplanets in part depends on the ability to differentiate between quasi-static speckles caused by aberrations not corrected by adaptive optics (AO) systems, known as…

Instrumentation and Methods for Astrophysics · Physics 2018-07-13 Alexander T. Rodack , Jared R. Males , Olivier Guyon , Benjamin A. Mazin , Michael P. Fitzgerald , Dimitri Mawet

We propose and implement an aberration correction method for the creation of extended arrays of spots well beyond the isoplanatic region of any optical system. The method relies on an extensive calibration of aberrations in terms of Zernike…

Optics · Physics 2025-12-19 Yohann Machu , Gautier Creutzer , Clément Sayrin , Michel Brune

The optics of any camera degrades the sharpness of photographs, which is a key visual quality criterion. This degradation is characterized by the point-spread function (PSF), which depends on the wavelengths of light and is variable across…

Image and Video Processing · Electrical Eng. & Systems 2022-08-02 Thomas Eboli , Jean-Michel Morel , Gabriele Facciolo

This paper reported a general noninterferometric high-accuracy quantitative phase imaging (QPI) method for arbitrary complex valued objects. Given by a typical 4f optical configuration as the imaging system, three frames of small-window…

Image and Video Processing · Electrical Eng. & Systems 2021-05-05 Jianhui Huang , An Pan , Huiliang Jin , Guoxiang Meng , Qian Ye

We introduce new linear mathematical formulations to calculate the focal length of a camera in an active platform. Through mathematical derivations, we show that the focal lengths in each direction can be estimated using only one point…

Computer Vision and Pattern Recognition · Computer Science 2018-06-12 Mehdi Faraji , Anup Basu

Fabry-P\'erot (FP) cavities are fundamental and ubiquitous optical elements frequently used in various sensing applications. Here, we introduce a general theoretical framework to study arbitrary light-cavity mode interactions for planar FPs…

Optics · Physics 2020-07-21 Jakub Czuchnowski , Robert Prevedel

In imaging modalities recording diffraction data, the original image can be reconstructed assuming known phases. When phases are unknown, oversampling and a constraint on the support region in the original object can be used to solve a…

Signal Processing · Electrical Eng. & Systems 2018-10-17 Alberto Pietrini , Carl Nettelblad

The use of Wavefront Sensors (WFS) is nowadays fundamental in the field of instrumental optics. This paper discusses the principle of an original and recently proposed new class of WFS. Their principle consists in evaluating the slopes of…

Optics · Physics 2011-05-23 Francois Henault

{We report on an intensity-only and deep-learning based method for laser beam characterization that allows to predict the underlying optical field within milliseconds. A simple near-field / far-field camera setup enables online control of…

With a Bayesian approach, the linear optics correction algorithm for storage rings is revisited. Starting from the Bayes' theorem, a complete linear optics model is simplified as "likelihood functions" and "prior probability distributions".…

Accelerator Physics · Physics 2019-04-18 Yongjun Li , Robert Rainer , Weixing Cheng

Vectorial adaptive optics (V-AO) is a cutting-edge technique extending conventional AO into the vectorial domain encompassing both polarization and phase feedback correction for optical systems. However, previous V-AO approaches focus on…

Optics · Physics 2023-12-12 Yifei Ma , Zimo Zhao , Jiahe Cui , Jingyu Wang , Chao He