Acoustic beam steering by light refraction: Illustration with directivity patterns of a tilted volume photoacoustic source
Langue
en
Article de revue
Ce document a été publié dans
Journal of the Acoustical Society of America. 2013-12, vol. 134, n° 6, p. 4381 - 4392
Acoustical Society of America
Résumé en anglais
The symmetry of a thermoelastic source resulting from laser absorption can be broken when the direction of light propagation in an elastic half-space is inclined relatively to the surface. This leads to an asymmetry of the ...Lire la suite >
The symmetry of a thermoelastic source resulting from laser absorption can be broken when the direction of light propagation in an elastic half-space is inclined relatively to the surface. This leads to an asymmetry of the directivity patterns of both compressional and shear acoustic waves. In contrast to classical surface acoustic sources, the tunable volume source allows one to take advantage of the mode conversion at the surface to control the directivity of specific modes. Physical interpretations of the evolution of the directivity patterns with the increasing light angle of incidence and of the relations between the preferential directions of compres-sional-and shear-wave emission are proposed. In order to compare calculated directivity patterns with measurements of normal displacement amplitudes performed on plates, a procedure is proposed to transform the directivity patterns into pseudo-directivity patterns representative of the experimental conditions. The comparison of the theoretical with measured pseudo-directivity patterns demonstrates the ability to enhance bulk-wave amplitudes and to steer specific bulk acoustic modes by adequately tuning light refraction.< Réduire
Mots clés en anglais
4320Rz
number(s): 4338Zp
4335Cg
4335Ud [ANN] Pages: 4381-4392
Origine
Importé de halUnités de recherche