Results 121 to 130 of about 1,516 (173)
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Solution to the Fresnel Zone Plate Problem
American Journal of Physics, 1969The diffraction problem for the Fresnel half-period zone plate is solved. The zone plate behaves as a lens with marked chromatism which can be taken advantage of for use in a spectrometer. The multiplicity of foci associated with the zone plate are examined in detail, and it is shown that the spectral range that can be focused without overlap is 3λmin ...
H. Malcolm Childers, David E. Stone
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Offset Fresnel zone plate antennas
International Journal of Satellite Communications and Networking, 1994AbstractThe theory of offset Fresnel zone plate antennas is presented. Explicit formulae for the design of the zone boundaries for the offset Fresnel zone plate are given. Theorectical equations and numerical results for the far‐field analysis are presented.
Y. J. Guo, S. K. Barton
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Dielectrophoretically controlled Fresnel zone plate
Lab on a Chip, 2015We present a novel switchable Fresnel zone plate, created using nanoparticle suspensions which are controlled by dielectrophoresis.
A F, Chrimes +4 more
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The Bandwidth of Fresnel-Zone Plate Antennas
Journal of Electromagnetic Waves and Applications, 1997Theoretical expressions are presented for the illumination and phase efficiency of three types of Fresnel-zone plate antennas. Using these formulas, the bandwidths of the antennas will be analyzed and compared. Measured data are given to validate the theoretical results.
van Houten, J.M., Herben, M.H.A.J.
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Contrast optimization of Fresnel zone plate imaging
Review of Scientific Instruments, 2023Fresnel zone plates (FZPs) are circular diffractive elements that operate as a lens for x-rays. They have gained interest in the field of laser-plasma physics due to their ability to achieve higher spatial resolution than pinholes. Their design and implementation are complicated by the fact that a significant amount of the x-rays passing through the ...
D. Haberberger +4 more
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Journal of Optics A: Pure and Applied Optics, 2009
The performance of Fresnel zone plates having a polygonal boundary between zones has been studied. The contribution of the complex amplitude of each zone is calculated analytically and numerically solved. The case of a continuous phase plate is considered as the limit case in performance for each polygonal shape.
Javier Alda, Francisco Javier González
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The performance of Fresnel zone plates having a polygonal boundary between zones has been studied. The contribution of the complex amplitude of each zone is calculated analytically and numerically solved. The case of a continuous phase plate is considered as the limit case in performance for each polygonal shape.
Javier Alda, Francisco Javier González
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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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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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SPIE Proceedings, 1985
A description is given of the use of the Fresnel zone plate as a focusing or a frequency-filtering device at millimeter wavelengths. Sample design data are given, as well as references to prior results. A newer type of zone plate is discussed which employs two dielectrics of equal thickness to produce a flat zone plate.
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A description is given of the use of the Fresnel zone plate as a focusing or a frequency-filtering device at millimeter wavelengths. Sample design data are given, as well as references to prior results. A newer type of zone plate is discussed which employs two dielectrics of equal thickness to produce a flat zone plate.
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Array illumination of a Fresnel–Dammann zone plate
Applied Optics, 2016The traditional Dammann grating is a phase-only modulation, and its theoretical foundation is based on far-field diffraction. Here we extend the traditional Fresnel zone plate (FZP) into a Fresnel-Dammann zone plate (FDZP), which is, in essence, considered as a FZP with Dammann modulation.
Yayao, Ma +5 more
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