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Fresnel zone interferometric imaging
Conference Proceedings. LEOS'98. 11th Annual Meeting. IEEE Lasers and Electro-Optics Society 1998 Annual Meeting (Cat. No.98CH36243), 2002We describe how Fourier analysis in projective coordinates allows inversion in the Fresnel zone. Since the longitudinal resolution of 3D coherence imaging falls inversely in the square of range in both the Fresnel and Fraunhofer zones, extension to the Fresnel zone dramatically improves longitudinal resolution by removing far-field range constraints in
D.J. Brady, D.L. Marks, R. Stack
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The Journal of the Acoustical Society of America, 1997
The notion of Fresnel zones for modes is introduced which is analogous to the usual Fresnel zones introduced for rays. It is shown that by using Fresnel zones for modes one can simplify the analysis of mode scattering at large-scale inhomogeneities in multimode waveguides.
Anatoly L. Virovlyansky +3 more
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The notion of Fresnel zones for modes is introduced which is analogous to the usual Fresnel zones introduced for rays. It is shown that by using Fresnel zones for modes one can simplify the analysis of mode scattering at large-scale inhomogeneities in multimode waveguides.
Anatoly L. Virovlyansky +3 more
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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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Fresnel-zone binning: Fresnel-zone shape with offset and velocity function
GEOPHYSICS, 2010The concept of the Fresnel zone has been explored by many workers; most commonly, their work has involved examining the Fresnel zone in the limiting case of zero offset and constant velocity. I have examined the shape of the Fresnel zone for nonzero offset and in the situation of constant velocity gradient. Finite-offset Fresnel zones are not circular
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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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Fresnel zones in inhomogeneous media
The Journal of the Acoustical Society of America, 2006A simple general expression for the width of a Fresnel zone in a smooth inhomogeneous environment is derived. In a stratified environment at long range, the general expression is shown to reduce approximately to one that is proportional to √|α|r(R−r)/f, where α is the ray stability parameter, f is the acoustic frequency, r is the range to the field ...
Irina I. Rypina, Michael G. Brown
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Acoustic Fresnel zone plate transducers
Applied Physics Letters, 1974Experimental focal plane intensity distributions are presented for a 10-zone acoustic zone plate operating at approximately 10 MHz. The results are related to the spatial frequency response of the transducer. Some initial imaging experiments with this transducer are described along with preliminary results for an acoustic phase plate.
S. A. Farnow, B. A. Auld
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Fresnel zones for broadband data
GEOPHYSICS, 1996For monochromatic waves, the term “Fresnel zone” is well‐defined even though different authors use different terminology. Most authors use the definition originating from optics. There, the first Fresnel zone is defined as the area of a circular hole in a screen between a light source and an observation point that produces maximum light intensity in ...
Matthias Brühl +2 more
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2002
In the preceding chapters, theoretical investigations and experiments on a number of Fresnel zone antennas are presented. This chapter is intended to introduce a wider range of Fresnel zone antennas. Section 7.1 presents a theory regarding the possibility of producing single printed Fresnel lens that doubles the efficiency of the simple Fresnel lens ...
Y. Jay Guo, Stephen K. Barton
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In the preceding chapters, theoretical investigations and experiments on a number of Fresnel zone antennas are presented. This chapter is intended to introduce a wider range of Fresnel zone antennas. Section 7.1 presents a theory regarding the possibility of producing single printed Fresnel lens that doubles the efficiency of the simple Fresnel lens ...
Y. Jay Guo, Stephen K. Barton
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Solid immersion Fresnel zone plate
Digital Holography & 3-D Imaging Meeting, 2015A solid immersion Fresnel zone plate (SIFZP) is designed and its near-field imaging characteristics are analyzed using the vector angular spectrum method. Results show SIFZP can generate a high intensity and subwavelength focus.
Yaoju Zhang +3 more
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