Results 21 to 30 of about 5,049 (222)

Dual-band and dual-polarized reflective Fresnel zone plate design based on Fractal shape

Scientific Reports, 2023
In this study, a dual-polarized and dual band reflective Fresnel zone plate with reconfigurable beam is proposed on the basis of fractal frequency selective surface (FSS) unit with nearly 360° phase tunability.
Lusong Wei, Chao Ma, Xingyu Liu, Hongbin Ma, Yuting Wu, Zhanchun Fan, Jiangtao Huangfu   +6 more
doaj   +1 more source

Fresnel coherent diffraction tomography

Optics Express, 2010
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Putkunz, Corey., Pfeifer, Mark., Peele, Andrew., Williams, G., Quiney, H., Abbey, Brian., Nugent, K., McNulty, Ian.   +7 more
openaire   +2 more sources

Equivalence of knife‐edge diffraction model and uniform geometrical theory of diffraction applying Fresnel approximation for an absorbing screen [PDF]

, 2023
Xin Du, Jun‐ichi Takada
openalex   +3 more sources

The colibri telescope array for KBO detection through serendipitous stellar occultations: A technical description

Frontiers in Astronomy and Space Sciences, 2022
We present the technical design, construction and testing of the Colibri telescope array at Elginfield Observatory near London, Ontario, Canada. Three 50-cm telescopes are arranged in a triangular array and are separated by 110–160 m.
Michael J. Mazur, Stanimir Metchev, Stanimir Metchev, Rachel A. Brown, Rachel A. Brown, Ridhee Gupta, Richard Bloch, Tristan Mills, Emily Pass   +8 more
doaj   +1 more source

Um experimento simples usado na produção de placas de zonas de Fresnel

Revista Brasileira de Ensino de Física
Neste trabalho propomos um experimento simples que tem por finalidade auxiliar no aprendizado dos fenômenos de interferência e difração da luz. Após uma análise pertinente da teoria de Fresnel da difração, os conhecimentos são aplicados na compreensão do
Márcia Muller, Jean Carlos Cardozo da Silva, José Luís Fabris   +2 more
doaj   +1 more source

Fresnel diffraction from sector apertures

Optics Express, 2021
The derivation of the analytic representation of the diffraction field from the sector aperture in the Fresnel zone is presented. The new solution is expressed in the form of a convergent series on incomplete cylindrical functions in the Poisson form that makes it possible to calculate and obtain three-dimensional patterns of the field amplitude in the
openaire   +2 more sources

Improvement of Fresnel Diffraction Convolution Algorithm

Applied Sciences
With the development of digital holography, the accuracy requirements for the reconstruction phase are becoming increasingly high. The transfer function of the double fast transform (D-FFT) algorithm is distorted when the diffraction distance is larger ...
Cong Ge, Qinghe Song, Weinan Caiyang, Jinbin Gui, Junchang Li, Xiaofan Qian, Qian Li, Haining Dang   +7 more
doaj   +1 more source

Optical Image Encryption Using a Nonlinear Joint Transform Correlator and the Collins Diffraction Transform

Photonics, 2019
The Collins diffraction transform (CDT) describes the optical wave diffraction from the generic paraxial optical system. The CDT has as special cases the diffraction domains given by the Fourier, Fresnel and fractional Fourier transforms.
Juan M. Vilardy O., Ronal A. Perez, Cesar O. Torres M.   +2 more
doaj   +1 more source

A Fourier-invariant squared Laguerre-Gaussian vortex beam

Компьютерная оптика, 2023
It is shown that a squared Laguerre-Gaussian (LG) vortex beam is Fourier-invariant and retains its structure at the focus of a spherical lens. In the Fresnel diffraction zone, such a beam is transformed into superposition of conventional LG beams, the ...
E.S. Kozlova, A.A. Savelyeva, A.A. Kovalev, V.V. Kotlyar   +3 more
doaj   +1 more source

The Fresnel Approximation and Diffraction of Focused Waves

Photonics
In this paper, diffraction of scalar waves by a screen with a circular aperture is explored, considering the incidence of either a collimated beam or a focused wave, a historical review of the development of the theory is presented, and the introduction ...
Colin J. R. Sheppard
doaj   +1 more source