Material characterization by the line--focus-beam (LFB) acoustic microscopy is made by measuring the propagation characteristics, viz., velocity and attenuation, of leaky surface acoustic wave (LSAW), excited on the water-loaded specimen surface, thorough V(z) curve analysis. In order to discuss the absolute accuracy, a method of system calibration has been proposed. In this calibration method, it is necessary to introduce nonpiezoelectric standard specimens whose bulk acoustic properties, i.e., independent elastic constants and density, are measured with high accuracy. The en-or factors in the measurements of bulk wave velocities and density, including diffraction effects on velocity measurement, are discussed in detail. Synthetic silica glasses, Gadolinium Gallium Garnet, Si, Ge are taken as standard specimens. Elastic constants and densities, and their temperature coefficients of standard specimens are measured around room temperature. LSAW propagation characteristics are measured and compared with the calculated results using the measured bulk acoustic properties. Calibration is demonstrated for the system using some LFB acoustic lens devices with a cylindrical concave surface of l -mm radius in the frequency range l 00)-300 MHz.
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