NOTICE: Due to a lapse in annual appropriations, most of this website is not being updated. Learn more.
Form submissions will still be accepted but will not receive responses at this time. Sections of this site for programs using non-appropriated funds (such as NVLAP) or those that are excepted from the shutdown (such as CHIPS and NVD) will continue to be updated.
An official website of the United States government
Here’s how you know
Official websites use .gov
A .gov website belongs to an official government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.
Optical Diffraction in Close Proximity to Plane Apertures. III. Modified, Self-Consistent Theory
Published
Author(s)
Klaus Mielenz
Abstract
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.
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 October 3, 2025)