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Zone plates for zero axial irradiance
Optics Letters, 1993We present a family set of zone plates for achieving zero axial irradiance at their foci. This kind of zone plate may be useful in optical alignment.
J, Ojeda-Castañeda, G, Ramírez
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Optically produced linear zone plates
Applied Optics, 1979Linear zone plates (LZP) have been constructed using optical methods both in amplitude and in phase. The results obtained confirm that focal distances follow the relation f/n, and the focal number and its diffraction efficiencies increase by transforming a LZP from amplitude to phase.
C, Gomez-Reino +2 more
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Zone Plates and Their Aberrations
Journal of the Optical Society of America, 1972The zone plate is an optical device that depends on interference, not reflection or refraction, for its image-forming properties. Although the irradiance at the focus is only 110 that of a lens with the same aperture, a zone plate with 100 or more zones is capable of resolution equal to that of the lens.
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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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Testing a zone plate with a grating interferometer
Applied Optics, 1990The physical theory, of testing optics by the Ronchi sine grating interferometer is developed. In the experiment a sine grating splits the third-order wavefront of the zone plate under test into three displaced wavefronts, which then interfere with one another to form interference fringes.
J A, Lin, W T, Yeh, S W, Hsu
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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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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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1975
If the waves protrayed in Figure 1.15 had been single-wavelength light waves, rather than sound waves, and if the two radiators had been long slits perpendicular to the paper, a white screen placed to the right of these slits would have displayed a comparable series of bright and dark vertical bands, called, in optical terminology, fringes.
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If the waves protrayed in Figure 1.15 had been single-wavelength light waves, rather than sound waves, and if the two radiators had been long slits perpendicular to the paper, a white screen placed to the right of these slits would have displayed a comparable series of bright and dark vertical bands, called, in optical terminology, fringes.
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An improved zoning rule of the Fresnel zone plate
Microwave and Optical Technology Letters, 1999In the traditional zoning rule of the Fresnel zone plate (FZP), the distance from two edges of each zone to a common focus is progressively increased with a half-wavelength step. In this paper, a more reasonable zoning rule is proposed to further increase the antenna gain by about 1 dB. ©1999 John Wiley & Sons, Inc. Microwave Opt Technol Lett 23: 69–73,
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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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