Results 181 to 190 of about 27,387 (213)
Some of the next articles are maybe not open access.
Fresnel zones in tapered gradient-index media
Journal of the Optical Society of America A, 2002The free propagation of a wave front in an inhomogeneous medium with parabolic refractive-index profile and the division of the wave front into Fresnel zones are studied. We determine the radius and the area of each zone as well as the zone contribution to the total wave at an observation point inside the medium.
José Manuel, Rivas-Moscoso +2 more
openaire +2 more sources
2003
In the context of Huygens' principle and physical optics, it makes sense to consider a volume over which the phase of contributing waves is fairly constant, centred around the line-of-sight where the phase is stationary. Consider the situation in Figure D.l where the distance between the two antennas is d and the total distance to a scattering point is
openaire +1 more source
In the context of Huygens' principle and physical optics, it makes sense to consider a volume over which the phase of contributing waves is fairly constant, centred around the line-of-sight where the phase is stationary. Consider the situation in Figure D.l where the distance between the two antennas is d and the total distance to a scattering point is
openaire +1 more source
Fresnel Zone-Plate Diffraction Patterns
Journal of the Optical Society of America, 1969The diffraction patterns of the central aperture and the first 10 rings of the classical Fresnel zone plate are calculated in the principal focal plane for off-axis distances as large as the radius of the 10th ring. The zone-plate pattern is found by summation; near the axis it is compared with closed-form approximations.
openaire +1 more source
Fresnel zone approach to self-Fourier transforming
Applied Optics, 1991The phenomenon of self-imaging and (in the case of coherent illumination) self-Fourier transforming was first observed over a century and a half ago. [H. Talbot, "Facts Relating to Optical Science NoIV.," Philos. Mag. 9,403-407 (1836).] There has since been a steady stream of publications in which the phenomenon has been noted and a theoretical ...
openaire +2 more sources
Sector-based Fresnel zone plate with extended depth of focus
Optics and Laser Technology, 2022Francisco Jose Torcal-Milla +2 more
exaly