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This Point spread function (PSF) plays a crucial role in many computational imaging applications, such as shape from focus/defocus, depth estimation, and fluorescence microscopy. However, the mathematical model of the defocus process is…

Computer Vision and Pattern Recognition · Computer Science 2022-09-20 Renzhi He , Yan Zhuang , Boya Fu , Fei Liu

The James Webb Space Telescope (JWST) Optical Simulation Testbed (JOST) is a tabletop experiment designed to reproduce the main aspects of wavefront sensing and control (WFSC) for JWST. To replicate the key optical physics of JWST's…

Instrumentation and Methods for Astrophysics · Physics 2015-06-22 Élodie Choquet , Olivier Levecq , Mamadou N'Diaye , Marshall D. Perrin , Rémi Soummer

Here we assess the spectral and imaging properties of Fabry P\'erot etalons when located in solar magnetographs. We discuss the chosen configuration (collimated or telecentric) for both ideal and real cases. For the real cases, we focus on…

Instrumentation and Methods for Astrophysics · Physics 2019-03-18 F. J. Bailén , D. Orozco Suárez , J. C. del Toro Iniesta

This study presents a comprehensive end-to-end simulation analysis of the optical imaging performance of the China Survey Space Telescope (CSST) under in-orbit conditions. An integrated system model incorporating five static and two dynamic…

Instrumentation and Methods for Astrophysics · Physics 2025-11-11 Zhang Ban , Xiao-Bo Li , Xun Yang , Yu-Xi Jiang , Hong-Cai Ma , Wei Wang , Jin-guang Lv , Cheng-Liang Wei , De-Zi Liu , Guo-Liang Li , Chao Liu , Nan Li , Ran Li , Peng Wei

(Abridged) Typically large telescope construction and operation costs scale up faster than their collecting area. This slows scientific progress, making it expensive and complicated to increase telescope size. A metric that represents the…

Instrumentation and Methods for Astrophysics · Physics 2020-11-25 Eran O. Ofek , Sagi Ben-Ami

High precision astrometry aims at source position determination to a very small fraction of the diffraction image size, in high SNR regime. One of the key limitations to such goal is the optical response variation of the telescope over a…

Instrumentation and Methods for Astrophysics · Physics 2021-04-08 Alberto Riva , Mario Gai , Alberto Vecchiato , Deborah Busonero , Mario G. Lattanzi , Federico Landini , Zhaoxiang Qi , Zhenghong Tang

We describe the design and performance of the SuMIRe Prime Focus Spectrograph (PFS) visible camera cryostats. SuMIRe PFS is a massively multi-plexed ground-based spectrograph consisting of four identical spectrograph modules, each receiving…

We developed a scan mirror mechanism (SMM) that enable a slit-based spectrometer or spectropolarimeter to precisely and quickly map an astronomical object. The SMM, designed to be installed in the optical path preceding the entrance slit,…

X-ray cone-beam computed tomography (CT) has the notable features such as high efficiency and precision, and is widely used in the fields of medical imaging and industrial non-destructive testing, but the inherent imaging degradation…

Optics · Physics 2015-06-19 Hua Zhang , Kuidong Huang , Yikai Shi , Zhe Xu

Recently introduced angular-memory-effect based techniques enable non-invasive imaging of objects hidden behind thin scattering layers. However, both the speckle-correlation and the bispectrum analysis are based on the statistical average…

Optics · Physics 2017-11-22 Tengfei Wu , Jonathan Dong , Xiaopeng Shao , Sylvain Gigan

Uncertainty in the wide-angle Point Spread Function (PSF) at large angles (tens of arcseconds and beyond) is one of the dominant sources of error in a number of important quantities in observational astronomy. Examples include the stellar…

In the imaging process of an astronomical telescope, the deconvolution of its beam or Point Spread Function (PSF) is a crucial task. However, deconvolution presents a classical and challenging inverse computation problem. In scenarios where…

Instrumentation and Methods for Astrophysics · Physics 2024-03-05 Shulei Ni , Yisheng Qiu , Yunchun Chen , Zihao Song , Hao Chen , Xuejian Jiang , Huaxi Chen

We present a practical apparatus for characterizing optical aberrations of large collimation mirrors and lenses, and give a detailed analysis of wavefront-detection errors. We utilize a scanning pentaprism technique for precise measurements…

Optics · Physics 2022-05-13 Youn Seok Lee , Kimia Mohammadi , Thomas Jennewein

The ultimate goal of the "Pi of the Sky" apparatus is observation of optical flashes of astronomical origin and other light sources variable on short timescales. We search mainly for optical emission of Gamma Ray Bursts, but also for…

Instrumentation and Methods for Astrophysics · Physics 2011-11-02 Lech Wiktor Piotrowski

We describe the symmetries present in the point-spread function (PSF) of an optical system either located in space or corrected by an adaptive o to Strehl ratios of about 70% and higher. We present a formalism for expanding the PSF to…

Modern Giant Segmented Mirror Telescopes (GSMT) like the Extremely Large Telescope (ELT), currently under construction depend heavily on Adaptive Optics (AO) systems to correct for atmospheric turbulence. To be able to correct wider fields…

Instrumentation and Methods for Astrophysics · Physics 2021-11-15 Roland Wagner , Daniela Saxenhuber , Ronny Ramlau , Simon Hubmer

The next generation of space-based telescopes used for weak lensing surveys will require exquisite point spread function (PSF) determination. Previously negligible effects may become important in the reconstruction of the PSF, in part…

Instrumentation and Methods for Astrophysics · Physics 2016-01-27 T. Kuntzer , F. Courbin , G. Meylan

One of the major limitations of adaptive optics (AO) corrected image post-processing is the lack of knowledge on the system point spread function (PSF). The PSF is not always available as a direct imaging on isolated point like objects such…

Instrumentation and Methods for Astrophysics · Physics 2020-07-22 Romain Fétick , Laurent Mugnier , Thierry Fusco , Benoit Neichel

Off-axis parabolic mirrors (OAPMs) are widely used in the THz and mm-wave communities for spectroscopy and imaging applications, as a result of their broadband, low-loss operation and high numerical apertures. However, the aspherical shape…

Optics · Physics 2023-11-07 Nishtha Chopra , James Lloyd-Hughes

We present a robust but still efficient simulation approach for high-resolution scanning tunneling microscopy with a flexible tip apex showing sharp submolecular features. The approach takes into account the electronic structure of sample…

Mesoscale and Nanoscale Physics · Physics 2017-01-11 O. Krejci , P. Hapala , M. Ondracek , P. Jelinek
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