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Fresnel Zone Number for Localization of Ground Plane
2024 IEEE Microwaves, Antennas, and Propagation Conference (MAPCON)Anil Kumar Yerrola, Maifuz Ali
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Unified and generalized Fresnel numbers
Optical and Quantum Electronics, 1992The concept of Fresnel number is discussed and expressions are derived for misaligned optical systems. For the case of perfectly aligned optical elements, the usual number,N, based on a Fresnel zone concept is found to be given byN = (a 2/λ)(D 1/B 1 +A 2/B 2), whereB 1,D 1 andB 2,A 2 are the transfer matrix elements of the optical systems before and ...
Shaomin Wang +2 more
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Fresnel number of a regular polygon and slit
Applied Optics, 2000The concept of the Fresnel number is generalized to make it possible to describe the regular polygon and slit illuminated by a homogeneous plane wave. The generalization is based on nonlinear regression of the axial intensity distribution curve. A useful analytical expression for the Fresnel number is presented.
S, Wang, Q, Lin, L, Yu, X, Xu
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Fabry–Perot Resonances at Small Fresnel Numbers
Applied Optics, 1964Abstract : A theory of Fabry-Perot resonances designed to be useful at small Fresnel numbers is given. This theory is applied to the case where the interferometer mirrors are of arbitrary curvature and have circular apertures. Asymptotic formulas are derived for the diffraction output and phase shifts in the limit of small Fresnel numbers.
S. R. Barone, M. C. Newstein
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Spectral anomalies in focused waves of different Fresnel numbers
Journal of the Optical Society of America A, 2004Light propagation induces remarkable changes in the spectrum of focused diffracted beams. We show that spectral changes take place in the vicinity of phase singularities in the focal region of spatially coherent, polychromatic spherical waves of different Fresnel numbers.
Carlos J, Zapata-Rodríguez +1 more
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Spatiotemporal Dynamics of Lasers with a Large Fresnel Number
Physical Review Letters, 1995We measure the local intensity and the intensity cross-correlation function of patterns emitted by a C${\mathrm{O}}_{2}$ laser with a Fresnel number around 60 and find evidence of weak turbulence. We show theoretically that the spatiotemporal dynamics of such a laser can be governed by two fields.
, Huyet, , Martinoni, , Tredicce, , Rica
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Dependence of Fresnel number on aperture stop position
Journal of the Optical Society of America A, 1998The influence of aperture stop position on the focusing properties of a lens is investigated. Expressions are obtained for the optical coordinates in terms of the system geometry. If the aperture stop is placed in the front focal plane of the lens, the effective Fresnel number is infinite.
C. J. R. Sheppard, P. Török
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Unstable resonators with negative equivalent Fresnel numbers
Optics Letters, 1986The equivalent Fresnel numbers of two unstable resonators of current interest for application in free-electron lasers are negative. For a resonator of this class, the equivalent collimated round-trip propagation of Siegman’s canonical formulation is a time-reversed propagation, and the modes and eigenvalues are the complex conjugates of those ...
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Fresnel region approximations for wide angles and large fresnel numbers
IEEE Transactions on Antennas and Propagation, 1966A general approximation is developed which permits the accurate computation of radiation patterns from circular apertures and reflectors by single integration both at wide angles and for large Fresnel numbers. Both the far-field and small angle Fresnel region approximations are obtained as special cases. The approximation is applicable to regions where
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