Synthetic aperture imaging by scanning acoustic microscopy with vector contrast

Based on phase sensitive scanning acoustic microscopy (PSAM), a novel scheme suitable for volume imaging has been developed. The method employs synthetic aperture insonification combined with synthetic aperture imaging. Excitation and detection are performed by planar scanning of two focusing transducer and vector (phase and amplitude) detectors for the ultrasonic wave packages observed in transmission. Examples for applications of the scheme, including technically relevant simplifications based on reduced dimensions of the scan ranges, are presented. Detection schemes already applied for nondestructive testing (NDT) and non-destructive evaluation (NDE) of the mechanical properties of functionally graded materials are an example for the application of the generalised approach presented here with reduced dimensions of the scan. The technique is suitable for NDT and NDE imaging respectively with three-dimensional resolution. (C) 2000 Elsevier Science B.V. All rights reserved.