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Optical Diffraction in Close Proximity to Plane Apertures. III. Modified, Self-Consistent Theory



Klaus Mielenz


The classical theory of diffraction by plane apertures illuminated by normally incident light is modified so that the diffraction on the source side of the screen is taken in to consideration and the optical field is continuous as well as continuously differentiable in the aperture plane. The modified field expressions involve the sums and differences of the Rayleigh-Sommerfeld diffraction integrals as descriptors of a bi-directional flow of energy in the near zones on either side of the aperture plane. The modified theory is valid for unpolarized fields and can be applied to metallic as well as black screens. In the mid zone it is reduced to the Fresnel approximation, and here the latter may be used with confidence. The modified field expressions are used for numerical near-field computations of the diffraction profiles and transmission coefficients of circular apertures and slits.
Journal of Research (NIST JRES) -
109 No. 5


bidirectional scalar fields, boundary-value theory, circular apertures, diffraction, irradiance, Kirchhoff, near zone, optics, polarization


Mielenz, K. (2004), Optical Diffraction in Close Proximity to Plane Apertures. III. Modified, Self-Consistent Theory, Journal of Research (NIST JRES), National Institute of Standards and Technology, Gaithersburg, MD (Accessed May 29, 2024)


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Created September 1, 2004, Updated February 17, 2017