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Conventional methods of wavefront reconstruction from the raw data of the Shack-Hartmann sensor use the focal spot shifts and discard the high-frequency information about the wavefront. Phase-retrieval-based methods treat the Hartmann…

In medical imaging, the diffusion models have shown great potential for synthetic image generation tasks. However, these approaches often lack the interpretable connections between the generated and real images and can create anatomically…

Image and Video Processing · Electrical Eng. & Systems 2026-02-12 Jian-Qing Zheng , Yuanhan Mo , Yang Sun , Jiahua Li , Fuping Wu , Ziyang Wang , Tonia Vincent , Bartłomiej W. Papież

In this article, we report an imaging method, termed Fourier ptychographic microscopy (FPM), which iteratively stitches together a number of variably illuminated, low-resolution intensity images in Fourier space to produce a wide-field,…

Optics · Physics 2014-05-02 Guoan Zheng , Roarke Horstmeyer , Changhuei Yang

Achieving high spatial resolution is the goal of many imaging systems. Designing a high-resolution lens with diffraction-limited performance over a large field of view remains a difficult task in imaging system design. On the other hand,…

An approach to diffraction tomography is investigated for two-dimensional image reconstruction of objects surrounded by an arbitrarily-shaped curve of sources and receivers. Based on the integral theorem of Helmholtz and Kirchhoff, the…

Mathematical Physics · Physics 2014-11-20 G. T. Clement

We present an analysis of six independent on-sky datasets taken with the Keck-II/NIRC2 instrument. Using the off-axis point spread function (PSF) reconstruction software AIROPA, we extract stellar astrometry, photometry, and other fitting…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Sean K. Terry , Jessica R. Lu , Paolo Turri , Anna Ciurlo , Abhimat Gautam , Tuan Do , Michael P. Fitzgerald , Andrea Ghez , Matthew Hosek , Gunther Witzel

4D-STEM, in which the 2D diffraction plane is captured for each 2D scan position in the scanning transmission electron microscope (STEM) using a pixelated detector, is complementing and increasingly replacing existing imaging approaches.…

Instrumentation and Detectors · Physics 2022-07-27 Colum M. O'Leary , Benedikt Haas , Christoph T. Koch , Peter D. Nellist , Lewys Jones

The ill-posed problem of phase retrieval in optics, using one or more intensity measurements, has a multitude of applications using electromagnetic or matter waves. Many phase retrieval algorithms are computed on pixel arrays using discrete…

Image and Video Processing · Electrical Eng. & Systems 2022-09-21 J. A. Pollock , K. S. Morgan , L. C. P. Croton , M. K. Croughan , G. Ruben , N. Yagi , H. Sekiguchi , M. J. Kitchen

We use camera-in-the-loop calibration to calibrate a phase-only spatial light modulator (SLM) in a far-field hologram setup. The recorded intensity distributions achieve a high degree of consistency with the calculated results, indicating a…

Optics · Physics 2026-02-18 Markus Zimmermann , Andreas Brenner , Tobias Haist , Stephan Reichelt

Optical astronomical images are strongly affected by the point spread function (PSF) of the optical system and the atmosphere (seeing) which blurs the observed image. The amount of blurring depends both on the observed band, and on the…

Instrumentation and Methods for Astrophysics · Physics 2023-08-31 Hong Wang , Sreevarsha Sreejith , Yuewei Lin , Nesar Ramachandra , Anže Slosar , Shinjae Yoo

This paper considers the problem of single image depth estimation. The employment of convolutional neural networks (CNNs) has recently brought about significant advancements in the research of this problem. However, most existing methods…

Computer Vision and Pattern Recognition · Computer Science 2018-09-25 Junjie Hu , Mete Ozay , Yan Zhang , Takayuki Okatani

We propose a wavefront-based method to estimate the PSF over the whole field of view. This method estimate the aberrations of all the mirrors of the telescope using only field stars. In this proof of concept paper, we described the method…

Instrumentation and Methods for Astrophysics · Physics 2016-08-08 Ferréol Soulez , Frédéric Courbin , Michael Unser

Diffusion models have established new state of the art in a multitude of computer vision tasks, including image restoration. Diffusion-based inverse problem solvers generate reconstructions of exceptional visual quality from heavily…

Image and Video Processing · Electrical Eng. & Systems 2024-08-21 Zalan Fabian , Berk Tinaz , Mahdi Soltanolkotabi

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

The accuracy in the photometry of a point source depends on the point-spread function (PSF), detector pixelization, and observing strategy. The PSF and pixel response describe the spatial blurring of the source, the pixel scale describes…

Instrumentation and Methods for Astrophysics · Physics 2012-02-02 Johan Samsing , Alex G. Kim

Light field cameras have a wide range of uses due to their ability to simultaneously record light intensity and direction. The angular resolution of light fields is important for downstream tasks such as depth estimation, yet is often…

Computer Vision and Pattern Recognition · Computer Science 2023-11-15 Langqing Shi , Ping Zhou

Deformable image registration is one of the fundamental tasks in medical imaging. Classical registration algorithms usually require a high computational cost for iterative optimizations. Although deep-learning-based methods have been…

Image and Video Processing · Electrical Eng. & Systems 2022-09-30 Boah Kim , Inhwa Han , Jong Chul Ye

Fourier ptychographic microscopy (FPM), characterized by high-throughput computational imaging, theoretically provides a cunning solution to the trade-off between spatial resolution and field of view (FOV), which has a promising prospect in…

Optics · Physics 2024-02-29 Shuhe Zhang , Aiye Wang , Jinghao Xu , Tianci Feng , Jinhua Zhou , An Pan

Image subtraction is essential for transient detection in time-domain astronomy. The point spread function (PSF), photometric scaling, and sky background generally vary with time and across the field-of-view for imaging data taken with…

Instrumentation and Methods for Astrophysics · Physics 2022-09-14 Lei Hu , Lifan Wang , Xingzhuo Chen , Jiawen Yang

Point Spread Function (PSF) for imaging through inhomogeneous refractive medium, such as atmospheric turbulence is bounded by three constraints [Charnotskii, Opt. Eng., 52, 04600, (2013)]. PSF is non-negative, band-limited, and the third…

Optics · Physics 2022-07-06 Mikhail Charnotskii