Results 241 to 250 of about 55,264 (288)

Chicago Aberration Correction Work

Microscopy and Microanalysis, 2011
Extended abstract of a paper presented at Microscopy and Microanalysis 2011 in Nashville, Tennessee, USA, August 7–August 11, 2011.
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Efficient parallel adaptive aberration correction

IEEE Transactions on Ultrasonics, Ferroelectrics and Frequency Control, 1998
Previous studies have shown that the parallel adaptive receive compensation algorithm (PARCA) can improve clinical images of the abdomen degraded by aberrations. Corrected images show both improved contrast resolution and overall image quality. However, PARCA is very computationally intensive and, consequently, cannot be easily implemented in real-time.
S, Krishnan, K W, Rigby, M, O'Donnell
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Lens Aberrations and Aberration Correction

2016
Aberrations in a lens refer to departure from the point-to-point imaging prescribed by the paraxial equation introduced in Chap. 6.
Jian Min Zuo, John C. H. Spence
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Lens Aberration Correction by Holography

Applied Optics, 1971
The correction of lens aberrations using a hologram made with a collimated reference is discussed. Two geometries in which the theoretical third-order hologram aberrations may be avoided are demonstrated. The results of experiments which demonstrate the aberration correction using the Ronchi and DeVany tests are presented.
J E, Ward, D C, Auth, F P, Carlson
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Historical aspects of aberration correction

Journal of Electron Microscopy, 2009
A brief history of the development of direct aberration correction in electron microscopy is outlined starting from the famous Scherzer theorem established in 1936. Aberration correction is the long story of many seemingly fruitless efforts to improve the resolution of electron microscopes by compensating for the unavoidable resolution-limiting ...
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Aberration Correction with Electron Mirrors

Journal of Applied Physics, 1949
Both the spherical and the chromatic aberration of electron microscope objectives may, in principle, be corrected with the aid of a uniform retarding field acting as a mirror. Such an arrangement has the drawback of requiring a conducting film in the ray path and the insertion of the specimen in a region of high field strength.
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Aberration-Corrected Plane Gratings

SPIE Proceedings, 1987
The aberrations present in a Czerny Turner monochromator employing spherical mirrors may be corrected by using a plane diffraction grating produced holographically and incorporating aberrations that exactly cancel those produced by the system concave mirrors.
A. Thevenon, J. Flamand, J. P. Laude, B. Touzet, J. Lerner   +4 more
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Aberration correction past and present

Philosophical Transactions of the Royal Society A: Mathematical, Physical and Engineering Sciences, 2009
Electron lenses are extremely poor: if glass lenses were as bad, we should see as well with the naked eye as with a microscope! The demonstration by Otto Scherzer in 1936 that skilful lens design could never eliminate the spherical and chromatic aberrations of rotationally symmetric electron lenses was therefore most unwelcome and the ...
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Progress in Aberration-Corrected High-Resolution Transmission Electron Microscopy Using Hardware Aberration Correction

Microscopy and Microanalysis, 2006
The design and construction of a double-hexapole aberration corrector has made it possible to build the prototype of a spherical-aberration corrected transmission electron microscope dedicated to high-resolution imaging on the atomic scale. The corrected instrument, a Philips CM200 FEG ST, has an information limit of better than 0.13 nm, and the ...
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Mechanically ruled aberration-corrected concave gratings

Applied Optics, 1980
Aberration-corrected concave gratings with curved and variable spacing grooves are ruled with a numerically controlled ruling engine. In the design of aberration-corrected concave gratings, mechanical methods allow more freedom to choose the amount of space variation than do holographic methods.
T, Harada, T, Kita
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