Results 261 to 270 of about 161,238 (304)
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Optics Communications, 1988
Abstract The phase contribution obtained by the superposition of two tilted wavefronts, one cylindrical and the other plane, is considered in this paper. It is shown that the obtained transmittance is equivalent to the conical lens transmittance. In the particular case, when the superposed wavefronts are collinear, the resulting hologram becomes an ...
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Abstract The phase contribution obtained by the superposition of two tilted wavefronts, one cylindrical and the other plane, is considered in this paper. It is shown that the obtained transmittance is equivalent to the conical lens transmittance. In the particular case, when the superposed wavefronts are collinear, the resulting hologram becomes an ...
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American Journal of Physics, 1962
A microwave zone plate not only illustrates some of the principles of optical (visible light) zone plates but exhibits also interesting differences which are due primarily to the wide aperture which is required for a practical microwave zone plate. These properties have been studied for a zone plate which was designed with four clear zones to focus 12 ...
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A microwave zone plate not only illustrates some of the principles of optical (visible light) zone plates but exhibits also interesting differences which are due primarily to the wide aperture which is required for a practical microwave zone plate. These properties have been studied for a zone plate which was designed with four clear zones to focus 12 ...
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Journal of Applied Physics, 1992
We present a novel application of the Fresnel zone plate geometry in which the Mössbauer effect is used to focus nuclear-resonant x-ray photons and thereby to monochromatize synchrotron radiation. The calculated efficiency and energy bandpass of the Mössbauer–Fresnel zone plate monochromator compare well with those of other Mössbauer-effect ...
T. M. Mooney, E. E. Alp, W. B. Yun
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We present a novel application of the Fresnel zone plate geometry in which the Mössbauer effect is used to focus nuclear-resonant x-ray photons and thereby to monochromatize synchrotron radiation. The calculated efficiency and energy bandpass of the Mössbauer–Fresnel zone plate monochromator compare well with those of other Mössbauer-effect ...
T. M. Mooney, E. E. Alp, W. B. Yun
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Optical Engineering, 1967
The properties of zone plates with different boundary shapes are considered. These shapes are discussed as special cases of the super ellipse. For each case the Fresnel-Kirchhoff diffraction integral is numerically evaluated. It is shown that an elliptical zone plate yields an astigmatic image with axial intensity peaks corresponding to the semi-major ...
Gary S. Waldman, Kenneth I. Clifford
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The properties of zone plates with different boundary shapes are considered. These shapes are discussed as special cases of the super ellipse. For each case the Fresnel-Kirchhoff diffraction integral is numerically evaluated. It is shown that an elliptical zone plate yields an astigmatic image with axial intensity peaks corresponding to the semi-major ...
Gary S. Waldman, Kenneth I. Clifford
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Laser Physics, 2018
We present a new family of diffractive lenses, Fibonacci-like zone plates, generated with a modified Fibonacci sequence. The focusing properties and the evolution of transverse diffraction pattern for the Fibonacci-like zone plates have been analytically investigated both theoretically and experimentally and compared with the corresponding Fresnel zone
Shubo Cheng +3 more
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We present a new family of diffractive lenses, Fibonacci-like zone plates, generated with a modified Fibonacci sequence. The focusing properties and the evolution of transverse diffraction pattern for the Fibonacci-like zone plates have been analytically investigated both theoretically and experimentally and compared with the corresponding Fresnel zone
Shubo Cheng +3 more
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Proceedings of the IEEE, 1966
Negative lens property responsible for reconstruction of original scene in full three- dimensional ...
W.E. Kock, L. Rosen, J. Rendeiro
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Negative lens property responsible for reconstruction of original scene in full three- dimensional ...
W.E. Kock, L. Rosen, J. Rendeiro
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IETE Journal of Research, 1968
ABSTRACTThe paper describes the design of a Fresnel zone plate suitable for use as an antenna in the centimetric or lower wavelength range. It has been shown that such antennas can be fabricated by using either metal or dielectric rings. Its properties have been analysed by employing the simple methods of electromagnetic diffraction.
G. S. Sanyal, Mahendra Singh
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ABSTRACTThe paper describes the design of a Fresnel zone plate suitable for use as an antenna in the centimetric or lower wavelength range. It has been shown that such antennas can be fabricated by using either metal or dielectric rings. Its properties have been analysed by employing the simple methods of electromagnetic diffraction.
G. S. Sanyal, Mahendra Singh
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1998
Publisher Summary The chapter discusses zone plates. Imaging in a projection or a probe (scanning) mode requires a focusing element. A lens is used for this purpose in visible and near-ultraviolet (W) light. In this case, the curvature of the surface and the effective diameter of the lens will be of the order of several microns.
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Publisher Summary The chapter discusses zone plates. Imaging in a projection or a probe (scanning) mode requires a focusing element. A lens is used for this purpose in visible and near-ultraviolet (W) light. In this case, the curvature of the surface and the effective diameter of the lens will be of the order of several microns.
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1986
In the previous chapter the imaging properties of amplitude and phase zone plates were considered, on the assumption that the zone boundaries were correctly positioned. These properties will be modified for realizable zone plates, since the boundaries cannot be positioned with arbitrary accuracy.
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In the previous chapter the imaging properties of amplitude and phase zone plates were considered, on the assumption that the zone boundaries were correctly positioned. These properties will be modified for realizable zone plates, since the boundaries cannot be positioned with arbitrary accuracy.
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