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Related papers: A Curvature-Compensated Corrector for Drift-Scan O…

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We discuss the design, construction, and use of a new class of scanning camera that eliminates a critical limitation of standard CCD drift-scan observations. A standard scan, which involves no correction for the differential drift rates and…

Astrophysics · Physics 2009-10-28 Dennis Zaritsky , Stephen A. Shectman , Gregory Bredthauer

In the present paper we consider quantitative estimation of the tolerances widening in optical systems with curved detectors. The gain in image quality allows to loosen the margins for manufacturing and assembling errors. On another hand,…

In this article, a new scanning electron microscopy (SEM) image composition technique is described, which can significantly reduce drift related image corruptions. Drift-distortion commonly causes blur and distortions in the SEM images.…

Instrumentation and Detectors · Physics 2010-08-09 Petr Cizmar , Andras E. Vladar , Michael T. Postek

Near-diffraction limited imaging and spectroscopy in the visible on large (8-10 meter) class telescopes has proved to be beyond the capabilities of current adaptive optics technologies, even when using laser guide stars. The need for high…

Instrumentation and Methods for Astrophysics · Physics 2015-05-19 Craig Mackay , Tim D. Staley , David King , Frank Suess , Keith Weller

Reliable quantitative analysis in scanning (transmission) electron microscopy (S(T)EM) is often hindered by image drift during long-duration spectral mapping for elemental analysis or for various material functions. We here present…

Instrumentation and Detectors · Physics 2026-04-22 Zac Thollar , Kanto Maeda , Tetsuya Kubota , Taka-aki Yano , Qiwen Tan , Takumi Sannomiya

The tilt, rotation, or offset of each CCD with respect to the focal plane, as well as the distortion of the focal plane itself, cause shape distortions to the observed objects, an effect typically known as field distortion (FD). We point…

Cosmology and Nongalactic Astrophysics · Physics 2019-04-24 Jun Zhang , Fuyu Dong , Hekun Li , Xiangchong Li , Yingke Li , Dezi Liu , Wentao Luo , Liping Fu , Guoliang Li , Zuhui Fan

Astronomers working with faint targets will benefit greatly from improved image quality on current and planned ground-based telescopes. At present, most adaptive optic systems are targeted at the highest resolution with bright guide stars.…

Instrumentation and Methods for Astrophysics · Physics 2020-01-30 Craig Mackay

Image distortion due to weak gravitational lensing is examined using a non-perturbative method of integrating the geodesic deviation and optical scalar equations along the null geodesics connecting the observer to a distant source. The…

General Relativity and Quantum Cosmology · Physics 2011-09-28 Thomas P. Kling , Louis Bianchini

In a scanning transmission electron microscope (STEM), producing a high-resolution image generally requires an electron beam focused to the smallest point possible. However, the magnetic lenses used to focus the beam are unavoidably…

We have developed a real-space method to correct distortion due to thermal drift and piezoelectric actuator nonlinearities on scanning tunneling microscope images using Matlab. The method uses the known structures typically present in…

Instrumentation and Detectors · Physics 2017-02-03 Mitchell P. Yothers , Aaron E. Browder , Lloyd A. Bumm

In order to further develop and implement novel drift scan imaging experiments to undertake wide field, high time resolution surveys for millisecond optical transients, an appropriate telescope drive system is required. This paper describes…

Instrumentation and Methods for Astrophysics · Physics 2021-08-18 S. J. Tingay

The brighter-fatter effect affects all CCD sensors to various degrees. Deep-depleted thick sensors are seriously affected and the measurement of galaxy shapes for cosmic shear measurements requires an accurate correction of the effect in…

Instrumentation and Methods for Astrophysics · Physics 2023-02-22 Pierre Astier , Nicolas Regnault

It is known that a relative translational motion between the deflector and the observer affects gravitational lensing. In this paper, a lens equation is obtained to describe such effects on actual lensing observables. Results can be easily…

Astrophysics · Physics 2008-11-26 M. Sereno

Flat-field images with thick, fully-depleted CCDs exhibit response variations near the edges of the chip and at other locations, such as the regoins bordering mid-frame blooming stop implants. Two possible origins for these repsonse…

Instrumentation and Methods for Astrophysics · Physics 2015-06-18 Paul O'Connor

The Large Synoptic Survey Telescope (LSST) will use an active optics system (AOS) to maintain alignment and surface figure on its three large mirrors. Corrective actions fed to the LSST AOS are determined from information derived from 4…

Instrumentation and Methods for Astrophysics · Physics 2015-10-26 Bo Xin , Chuck Claver , Ming Liang , Srinivasan Chandrasekharan , George Angeli , Ian Shipsey

Lidar point cloud distortion from moving object is an important problem in autonomous driving, and recently becomes even more demanding with the emerging of newer lidars, which feature back-and-forth scanning patterns. Accurately estimating…

Robotics · Computer Science 2022-07-05 Wen Yang , Zheng Gong , Baifu Huang , Xiaoping Hong

The availability of a robust and efficient routine for calculating light curves of a finite source magnified due to bending its light by the gravitational field of an intervening binary lens is essential for determining the characteristics…

Astrophysics · Physics 2008-11-26 M. Dominik

As the Universe expands, the redshift of distant sources changes with time. Here we discuss gravitational lensing phenomena that are consequence of the redshift drift between lensed source, gravitational lens, and observer. When the source…

Cosmology and Nongalactic Astrophysics · Physics 2022-06-01 Giovanni Covone , Mauro Sereno

A telescope specifically designed for the observation of the stellar aberration of light is proposed. It is distinctive in two main features: a lengthy collimated beam and an adjustable position of the photo-detector along the telescope…

General Physics · Physics 2007-05-23 G. Sardin

The bending of lightrays by the gravitational field of a ``lens'' that is moving relative to the observer is calculated within the approximation of weak fields, small angles and thin lenses. Up to first order in $v/c$ -- and assuming the…

Astrophysics · Physics 2009-11-07 Simonetta Frittelli
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