Materials Characterization by a Time-Resolved and Polarization-Sensitive Ultrasonic Technique

Since first developed by Lemons and Quate in 1973 [1], scanning acoustic microscopy has been able to obtain images comparable to those from a high quality optical microscope [2]. In the meantime, many investigators [3–7] have developed that technology to determine the microscopic properties of materials. Among those developments, the line-focus-beam (LFB) acoustic microscopy work of Kushibiki and Chubachi [6–7] in the early 1980’s has been most widely recognized [8–10]. Since the LFB technique is a directional measurement, it can be used to study material anisotropy and stress