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Tunable focusing properties using optofluidic Fresnel zone plates
Lab on a Chip, 2016This paper demonstrates the real-time tunable focusing properties of Fresnel zone plate using solid–liquid hybrid structure.
Y, Shi, X Q, Zhu, L, Liang, Y, Yang
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Millimeter-wave Fresnel zone plate antennas
SPIE Proceedings, 1994Fresnel zone plate antennas have seen extensive research in recent years. Both transmission and reflection types have been analyzed and tested, and found to give excellent performance. Parameters such as far-field patterns, gain, efficiency, frequency dependence, aberrations, scan capability, focal region properties, and off-axis performance have been ...
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[Thyroid scintigraphy with Fresnel zone plates].
Nuklearmedizin. Nuclear medicine, 1985Coded apertures supply a decoupling of resolution and sensitivity in scintigraphic imaging. The reconstructed images are focussed on different planes. The approach presented replaces the conventional collimator by three Fresnel zone plates in order to simulate a complex projection.
J, Meinke +2 more
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Variations on the Fresnel Zone Plate
Journal of the Optical Society of America, 1966The effects of contrast in the Fresnel zone plate on the amplitude in the focal point due to a normally incident plane wave are obtained by direct evaluation of the Fresnel–Kirchhoff diffraction integral. The change in focal-point amplitude due to smoothing the ordinary, discontinuous, “square-wave” transmission function into a continuous, “sine-wave ...
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Hard-x-ray microscopy with Fresnel zone plates reaches 40nm Rayleigh resolution
Applied Physics Letters, 2008Wah-Keat Lee
exaly
Birefringent Fresnel zone plates in silica fabricated by femtosecond laser machining
Optics Letters, 2002Peter G Kazansky
exaly