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Related papers: Dual-wavelength Fourier Ptychographic Topography

200 papers

Faraday tomography offers crucial information on the magnetized astronomical objects, such as quasars, galaxies, or galaxy clusters, by observing its magnetoionic media. The observed linear polarization spectrum is inverse Fourier…

Instrumentation and Methods for Astrophysics · Physics 2020-11-24 Suchetha Cooray , Tsutomu T. Takeuchi , Takuya Akahori , Yoshimitsu Miyashita , Shinsuke Ideguchi , Keitaro Takahashi , Kiyotomo Ichiki

We present a solution method which combines the method of matched asymptotics with the method of multipole expansions to determine the band structure of cylindrical Helmholtz resonators arrays in two dimensions. The resonator geometry is…

Fluid Dynamics · Physics 2022-02-22 M. J. A. Smith , I. D. Abrahams

Low-count positron emission tomography (PET) reconstruction is a challenging inverse problem due to severe degradations arising from Poisson noise, photon scarcity, and attenuation correction errors. Existing deep learning methods typically…

Image and Video Processing · Electrical Eng. & Systems 2026-04-09 Zheng Zhang , Hao Tang , Yingying Hu , Zhanli Hu , Jing Qin

Imaging an object embedded within a scattering medium requires the correction of complex sample-induced wave distortions. Existing approaches have been designed to resolve them by optimizing signal waves recorded in each 2D image. Here, we…

Optics · Physics 2022-10-17 Ye-Ryoung Lee , Dong-Young Kim , Yonghyeon Jo , Moonseok Kim , Wonshik Choi

Phase retrieval problems in antenna measurements arise when a reference phase cannot be provided to all measurement locations. Phase retrieval algorithms require sufficiently many independent measurement samples of the radiated fields to be…

Signal Processing · Electrical Eng. & Systems 2022-06-24 Josef Knapp , Alexander Paulus , Jonas Kornprobst , Uwe Siart , Thomas F. Eibert

Doppler orbitography uses the Doppler shift in a transmitted signal to determine the orbital parameters of satellites including range and range-rate (or radial velocity). We describe two techniques for atmospheric-limited optical Doppler…

Instrumentation and Methods for Astrophysics · Physics 2020-06-09 Benjamin P. Dix-Matthews , Sascha W. Schediwy , David R. Gozzard , Simon Driver , Karl Ulrich Schreibe , Randall Carman , Michael Tobar

Photomultiplier tubes (PMTs) are widely employed in particle and nuclear physics experiments. The accuracy of PMT waveform reconstruction directly impacts the detector's spatial and energy resolution. A key challenge arises when multiple…

High Energy Physics - Experiment · Physics 2026-02-06 Kainan Liu , Jingyu Huang , Guihong Huang , Jianyi Luo

Photomultiplier tubes (PMTs) are extensively employed as photosensors in neutrino and dark matter detection. The precise charge and timing information extracted from the PMT waveform plays a crucial role in energy and vertex reconstruction.…

Instrumentation and Detectors · Physics 2025-02-14 Jingzhe Tang , Tianying Xiao , Xuan Tang , Yongbo Huang

Diffraction limit is manifested in the loss of high spatial frequency information that results from decay of evanescent waves. As a result, conventional far-field optics yields no information about an object's subwavelength features. Here…

Optics · Physics 2012-01-24 Leonid Alekseyev , Evgenii Narimanov , Jacob Khurgin

The quadratic phase Fourier transform has gained much popularity in recent years because of its applications in image and signal processing. However, the QPFT is inadequate for localizing the quadratic phase spectrum which is required in…

Signal Processing · Electrical Eng. & Systems 2022-03-01 Mohd Younus Bhat , Aamir Hamid Dar , Didar Urynbassarova , Altyn Urynbassarova

Continuous wavefront sensing benefits space observatories in on-orbit optical performance maintenance. To measure the phase of a wavefront, phase retrieval is an attractive technique as it uses multiple point spread function (PSF) images…

Instrumentation and Methods for Astrophysics · Physics 2024-09-17 Hyukmo Kang , Kyle Van Gorkom , Meghdoot Biswas , Daewook Kim , Ewan S. Douglas

Ptychography is an enabling coherent diffraction imaging technique for both fundamental and applied sciences. Its applications in optical microscopy, however, fall short for its low imaging throughput and limited resolution. Here, we report…

An integrated photonic circuit architecture to perform a modified-convolution operation based on the Discrete Fractional Fourier Transform (DFrFT) is introduced. This is accomplished by utilizing two nonuniformly-coupled waveguide lattices…

Optics · Physics 2025-02-25 Kevin Zelaya , Mohammad-Ali Miri

We introduce the two-point propagation field (TPPF), a real-valued, phase-sensitive quantity defined as the functional derivative of the single-photon detection probability with respect to an infinitesimal opaque perturbation placed between…

Optics · Physics 2026-04-16 Li Hua Yu

Pan-Tilt-Zoom (PTZ) cameras with wide-angle lenses are widely used in surveillance but often require image rectification due to their inherent nonlinear distortions. Current deep learning approaches typically struggle to maintain…

Computer Vision and Pattern Recognition · Computer Science 2025-04-10 Teng Xiao , Qi Hu , Qingsong Yan , Wei Liu , Zhiwei Ye , Fei Deng

This article describes the FFTJet software package designed to perform jet reconstruction in the analysis of high energy physics experimental data. A two-stage approach is adopted in which pattern recognition is performed first, utilizing…

High Energy Physics - Experiment · Physics 2009-07-03 I. Volobouev

We develop a flexible feature selection framework based on deep neural networks that approximately controls the false discovery rate (FDR), a measure of Type-I error. The method applies to architectures whose first layer is fully connected.…

Machine Learning · Statistics 2026-02-10 Kazuma Sawaya

We investigate methods to calibrate the non-common path aberrations at an adaptive optics system having a wavefront-correcting device working at an extremely high resolution (larger than 150x150). We use focal-plane images collected…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Visa Korkiakoski , Christoph U. Keller , Niek Doelman , Matthew Kenworthy , Gilles Otten , Michel Verhaegen

The on-chip broadband optical spectrometers which cover the entire tissue transparency window ({\lambda}=650-1050 nm) with high resolution are highly demanded for the miniaturized bio-sensing and bio-imaging applications. Here, we propose a…

Optics · Physics 2021-12-15 Kyoung Min Yoo , Ray T. Chen

Fluorescence molecular tomography (FMT) is a sensitive optical imaging technology widely used in biomedical research. However, the ill-posedness of the inverse problem poses a huge challenge to FMT reconstruction. Although end-to-end deep…

Image and Video Processing · Electrical Eng. & Systems 2025-03-18 Peng Zhang , Qianqian Xue , Xingyu Liu , Guanglei Zhang , Wenjian Wang , Jiye Liang