A source laser 12 scans the surface of an object 14, such as an engineering material, and reflected ultrasonic waves are detected by a detector laser 16 and detector 18 such as a sensitive interferomic detector. The detected signals are captured 20, converted to digital signals 22 and stored in memory 24. The stored signals are processed in processor 26, using a synthetic aperture focusing technique (SAFT) which coherently sums the signals along a hyperbolic curve (32, fig. 2) for all the acoustic reflectors (30, fig. 2) within the object in order to image the object. In addition, low frequency components are filtered from detected laser ultrasound waveform data to further enhance resolution, SNR, and contrast. Geometric knowledge permits the generation of images of objects having a complex and arbitrary shape.
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