3rd French conference on acoustics
J. Phys. IV France 04 (1994) C5-1213-C5-1216
Signature V(z) en microscopie acoustique : influence de la non-uniformité de l'illumination du capteurG. DESPAUX, C. MAUREL, D. BARJON and J. ATTAL
Laboratoire de Microacoustique de Montpellier, Université de Montpellier II, Place Eugène Bataillon, SDI 5978 du CNRS, 34095 Montpellier, France
This paper deals with the improvement of the surface velocity measurements by removing the central part of the acoustic beam of a lens in defocusing configuration responsible for the V(z) acoustic signature. We investigate the influence of occulting the top of the lens by a circular stop of varying parameters. The V(z) is significantly affected but does not allow a complete decorrelation of the central beam. An alternative solution is proposed with a lens set at the half Fresnel length.
© EDP Sciences 1994