FINAL REPORT MAY 1, 1961 - JANUARY 14, 1970,
Abstract
The science of optics is founded on the fact that behavior of solutions of Maxwell's equations simplifies in the limit of small wavelengths. Moreover, geometrical principles give valid qualitative information even for wavelengths comparable to typical dimensions of the objects involved. Although this has been known for many years, it is only recently that, starting with the work of Luneberg, these ideas have been made quantitative and they have been systematically pursued. The most successful extension of geometrical optics is J. B. Keller's geometrical theory of diffraction, which now dominates the subject in both its practical and its theoretical aspects. Keller's methods are the mainstay of those concerned with scattering of electromagnetic waves by metallic objects. The bulk of the work on this contract has been devoted to refinement and extension of the methods of Luneberg and Keller. As a result of the work of Luneberg and Keller, with various extensions and modifications, methods are available to treat scattering by general bodies (smooth and convex, or with edges) and wave propagation and source problems in quite general media. These results can be applied in a great variety of situations, for example, to study waves in ionized media such as the ionosphere or the vicinity of reentry vehicles. These methods may also be used to study propagation of underwater acoustic waves and seismic waves.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 14, 1970
- Accession Number
- AD0708749
Entities
People
- Joseph B. Keller
Organizations
- New York University