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Wide angle near-field diffraction and Wigner distribution

J. B. Almeida·V. Lakshminarayanan
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Abstract

Free-space propagation can be described as a shearing of the Wigner distribution function in the spatial coordinate; this shearing is linear in paraxial approximation but assumes a more complex shape for wide-angle propagation. Integration in the frequency domain allows the determination of near-field diffraction, leading to the well known Fresnel diffraction when small angles are considered and allowing exact prediction of wide-angle diffraction. The authors use this technique to demonstrate evanescent wave formation and diffraction elimination for very small apertures.

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J. B. Almeida, V. Lakshminarayanan. 2003-05-08. Wide angle near-field diffraction and Wigner distribution. https://doi.org/10.1078/0030-4026-00272

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