Accession Number : ADA136321

Title :   Reflection Acoustic Microscopy for Micro-NDE.

Descriptive Note : Final technical rept. Jan 79-Mar 82,

Corporate Author : UNIVERSITY COLL LONDON (ENGLAND) DEPT OF ELECTRONIC AND ELECTRICAL ENGINEERING

Personal Author(s) : Nikoonahad,M

PDF Url : ADA136321

Report Date : Feb 1983

Pagination or Media Count : 160

Abstract : The reflection acoustic microscope has evolved to a stage where it can be regarded as a powerful laboratory tool for an important class of problems in non destructive examination. The report is concerned with an extension of the capability of the acoustic microscope for such applications. Acoustic microscopy involves imaging in highly attenuating media. There has for long been a controversy on whether the losses enhance or degrade the resolution of the microscope. The author has developed a novel analytical technique - an extension of Fourier optics - for analyzing this problem. Results obtained show that with losses: (i) The resolution deteriorates; (ii) The sidelobe levels at the focal plane are reduced and (iii) The depth of focus of the lens is reduced.

Descriptors :   *Acoustic microscopes, *Nondestructive testing, Fourier analysis, Optics, Resolution, Pulse compression, Diffraction, Apertures, Sidelobes, Focal planes, Subsurface, Ultrasonics, Reflection, Absorption, Fluids

Subject Categories : Test Facilities, Equipment and Methods
      Acoustics
      Optics

Distribution Statement : APPROVED FOR PUBLIC RELEASE