Three-Dimensional Imaging Using Spherical Ultrasound Wave Generated by Laser-Induced Breakdown

Abstract

In this paper, we propose a new framework of ultrasonic (US) three-dimensional (3D) imaging, introducing laser-induced breakdown (LIB) as an acoustic source. LIB is a phenomenon in which a substance is transformed to a plasma by a pulsed laser beam. LIB explosively emits a variety of energies such as heat, light and sound which also includes pulsed ultrasound. Emitted US waves have suitable characteristics for US 3D imaging in terms of low directivity, enabling a wide view and sharply pulsed waves. Utilizing these characteristics, we attempt to apply the synthetic aperture method for frontal 3D imaging in a real-time process. Experimental results show that even sparsely arrayed sensors allow a wider frontal view than that allowed in the case using existing transducers.