Air-coupled acoustic radiation force for non-contact generation of broadband mechanical waves in soft media

作者：Ambrozinski Lukasz; Pelivanov Ivan^*; Song Shaozhen; Yoon Soon Joon; Li David; Gao Liang; Shen Tueng T; Wang Ruikang K; O'Donnell Matthew

来源：Applied Physics Letters, 2016, 109(4): 043701.

DOI：10.1063/1.4959827

A non-contact method for efficient, non-invasive excitation of mechanical waves in soft media is proposed, in which we focus an ultrasound (US) signal through air onto the surface of a medium under study. The US wave reflected from the air/medium interface provides radiation force to the medium surface that launches a transient mechanical wave in the transverse (lateral) direction. The type of mechanical wave is determined by boundary conditions. To prove this concept, a home-made 1MHz piezo-ceramic transducer with a matching layer to air sends a chirped US signal centered at 1MHz to a 1.6mm thick gelatin phantom mimicking soft biological tissue. A phase-sensitive (PhS)-optical coherence tomography system is used to track/image the mechanical wave. The reconstructed transient displacement of the mechanical wave in space and time demonstrates highly efficient generation, thus offering great promise for non-contact, non-invasive characterization of soft media, in general, and for elasticity measurements in delicate soft tissues and organs in bio-medicine, in particular. Published by AIP Publishing.

• 出版日期2016-7-25