Open AccessShifted band-extended angular spectrum method for off-axis diffraction calculation
Author(s) -
Wenhui Zhang,
Hao Zhang,
Kyoji Matsushima,
Guofan Jin
Publication year - 2021
Publication title -
optics express
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.394
H-Index - 271
ISSN - 1094-4087
DOI - 10.1364/oe.419096
Subject(s) - optics , diffraction , angular spectrum method , physics , fresnel diffraction , paraxial approximation , offset (computer science) , bandwidth (computing) , fourier transform , computer science , telecommunications , beam (structure) , quantum mechanics , programming language
The shifted band-extended angular spectrum method (Shift-BEASM) is proposed to calculate free-space diffraction between two parallel planes with an off-axis offset. Off-axis numerical propagation is useful for simulating non-paraxial and large-scale fields. The proposed Shift-BEASM allow us to calculate the off-axis diffraction in a wide propagation range by extending the effective bandwidth using the nonuniform fast Fourier transform. The calculation accuracy is higher than that of existing techniques, such as the shifted-Fresnel method and shifted band-limited angular spectrum method, not only in the near field but also in the far field. Numerical examples and accuracy as well as theoretical formulation are presented to confirm validity of the proposed method.