Title :
A closer examination of Fresnel and Fraunhofer regions in the scalar wave diffraction theory
Author_Institution :
Dept. of Electr. & Comput. Eng., California State Univ., Chico, CA, USA
Abstract :
The regions of validity for both the Fresnel and the Fraunhofer diffraction regions are examined. The neglected phase terms in the general formalism of scalar diffraction theory are attributed to the secondary Huygens´s sources over the aperture and a geometrical argument leads to an equation of a curve defining the Fresnel region. It is found that the boundary profile of the cone-like Fresnel region is a slowly varying function of three-fourths the power of z, the direction of wave propagation. Both the Fresnel and the Fraunhofer regions are deduced from a simple phase error criterion and we find them to be the solids of rotation bounded by the z to the three-fourths power curve
Keywords :
Fraunhofer diffraction; Fresnel diffraction; light diffraction; light propagation; physical optics; Fraunhofer diffraction regions; Fresnel diffraction regions; aperture; boundary profile; cone-like Fresnel region; curve; geometrical argument; neglected phase terms; optical field; phase error criterion; rotation solids; scalar wave diffraction theory; secondary Huygens´s sources; slowly varying function; wave propagation; Apertures; Electromagnetic diffraction; Electromagnetic fields; Electromagnetic scattering; Green´s function methods; Laplace equations; Linear systems; Optical surface waves; Partial differential equations; Surface waves;
Conference_Titel :
System Theory, 1995., Proceedings of the Twenty-Seventh Southeastern Symposium on
Conference_Location :
Starkville, MS
Print_ISBN :
0-8186-6985-3
DOI :
10.1109/SSST.1995.390527
