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Preventing Coma Aberration by Annular Apodizer for Optical Disk Tilting
Japanese Journal of Applied Physics, 1999This research was carried out to determine the optimum parameters for an optical apodizer, applicable to a pick-up head for higher recording density optical disks. The coma aberration generated by tilting a disk increases the side-lobe intensity of the beam waist spot, and the increased side-lobe portion of the beam waist spot ...
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Applied Optics, 1985
Diffraction image of a point source due to an optical system with residual primary coma and nonuniform amplitude transmission is studied in order to obtain a suitable expression for the fractional encircled energy distribution in the Fraunhofer plane.
S C, Biswas, J E, Villeneuve
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Diffraction image of a point source due to an optical system with residual primary coma and nonuniform amplitude transmission is studied in order to obtain a suitable expression for the fractional encircled energy distribution in the Fraunhofer plane.
S C, Biswas, J E, Villeneuve
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Optical transfer functions in the presence of primary coma
Proceedings of the Physical Society, 1965An interferometric method for measuring the modulus and phase of the optical transfer function is described. A simple lens having seven wavelengths of primary coma, and negligible values of other aberrations, has been designed for use in monochromatic light. Using this lens, the computed modulus and phase of the transfer function have been measured for
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Coma-free alignment of high resolution electron microscopes with the aid of optical diffractograms
Ultramicroscopy, 1978Alignment by means of current commutating and defocusing of the objective does not yield the desired rotational symmetry of the imaging pencils. This was found while aligning a transmission electron microscope with a single field condenser objective. A series of optical diffractograms of micrographs taken under the same tilted illumination yet under ...
F. Zemlin +4 more
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X-Ray Structure of the Coma Cluster from Optical Data
1980The work I am going to describe was carried out in Oxford and Amherst in collaboration with 0. Strimpel. A full account will be found in Binney and Strimpel(1978) and in Strimpel and Binney(1979).
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An easy-to-use Model for the Optical Thickness and Ambient Illumination within Cometary Dust Comae
Earth, Moon, and Planets, 2002We define a procedure which allows estimation of the optical thickness of a cometary dust coma and the ambient illumination of the nucleus for any given comet, if estimates of the nucleus radius and the dust activity (A f ρ) are available. The calculation is performed for a singly scattering coma with a cos(ϑ) distribution of dust over its day side. We
Michael Müller +2 more
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Elemental Composition and Optical Properties of Cometary Dust Particles in the Coma of Comet 67P
2022<p>The COmetary Secondary Ion Mass Analyser (COSIMA) instrument on board ESA's Rosetta mission to comet 67P/Churyumov&#8211;Gerasimenko has collected and analysed dust particles in the inner coma from August 2014 to September 2016 between 1.25 and 3.8 AU solar distance and 4 to 1000 km off the comet nucleus.
Martin Hilchenbach +2 more
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A comparison of X-ray and optical wavelet maps in the central region of coma
AIP Conference Proceedings, 1995We have applied a wavelet transform analysis on ROSAT images and on an optical catalouge of the Coma cluster of galaxies. The comparison of these two sets of images allows us a detection of X‐ray emitting galaxies as well as particular emitting regions.
D. Gerbal +7 more
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The Influence of Coma on the Response Function of an Optical System
Proceedings of the Physical Society, 1960The treatment used in a previous paper dealing with the effect of spherical aberration on optical response functions has been extended to cases of coma, an aberration which is not an even function in the pupil coordinates x and y, and consequently gives rise to lateral shifting in the image.
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Diffraction patterns of off-axis gaussian beams in the optical system with astigmatism and coma
Optics Communications, 1978Abstract Fraunhofer diffraction patterns of off-axis gaussian beams passing through the optical system having either astigmatism together with the longitudinal focal shift or coma are investigated. When the optical system involves primary astigmatism with the longitudinal focal shift, the resultant diffraction patterns show an elliptic or ...
A. Yoshida, T. Asakura
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