Portal de Periódicos da CAPES

Optimal Filter Design for Annular Imaging

1974; Optica Publishing Group; Volume: 13; Issue: 12 Linguagem: Inglês

10.1364/ao.13.002919

0003-6935

A. Fedotowsky, K. Lehovec,

Seismic Imaging and Inversion Techniques

Filters of the type exp(in theta)sgn J(n)(z(o)r) with theta the azimuthal angle and r the radial coordinate in the filter plane, are shown to maximize the energy content in a narrow annular image of radius z(o) with respect to incident energy. The simplest optimal filter, sgnJ(o)(z(o)r), is well approximated by the binary circular phase grating sgn cos(z(o)r - pi/4). The single lobe of the first order image of this filter contains 46% of the incident energy within the half-width 0.4lambdaf/a, centered around the image radins Nlambdaf/(2a), where N approximately z(o)/pi is the number of filter sections.