Experimental work at the University of Utah has produced high-resolution optical diffraction patterns by slit apertures, 20 m from source and 30 m from photomultiplier receiver slit. The slit widths varied in 26 values from 0.5 to 32 mm with 4358- and 5461-Å light, corresponding to a Fresnel-variable difference ranging from 0.271 to 19.396. The receiver-slit width was 0.2 mm. A versatile program developed at The Aerospace Corporation for calculation of Fresnel integrals has been used for comparison with experiment, including averaging to give the effect of integration by the photomultiplier slit. Experimental and theoretical diffraction curves are compared for various slit widths. One double-slit-pattern comparison is also given. A high degree of symmetry is found in the measured curves. Even the very fine fluctuations of irradiance in the experimental and theoretical curves match. Three-dimensional theoretical projections of diffraction patterns show the continuous change of pattern from near-Fraunhofer to Fresnel diffraction.
FRANKLIN S. HARRIS JR., MICHAEL S. TAVENNER, and RICHARD L. MITCHELL, "Single-Slit Fresnel Diffraction Patterns: Comparison of Experimental and Theoretical Results," J. Opt. Soc. Am. 59, 293-295 (1969)