The scanning laser acoustic microscope (SLAM) has recently been equipped with a quadrature detector for holographic signal detection. It has been determined that data acquisition error often exists in the quadrature detector output. The resulting degradation in the reconstructed images is in the form of a fixed-frequency background fluctuation in the laser scar direction. The authors present an algorithm for the estimation and correction of the data acquisition error for the purpose of resolution improvement. The error is estimated by comparing the single-sideband wave-field signals of the quadrature output pair. The error correction is achieved by a matrix operator applied to the output pair. Examples involving experimental data are included to demonstrate the removal of the wave-field error and the improved resolution of the reconstructed images.>

System performance is substantially enhanced by using good attenuators in the system and employing a pulsing mode of operation. Spurious image elements, due to multiple reflections of the ultrasound in the acoustic cell and due to echoes from elements in the system which are not part of the object plane being imaged, can be eliminated in this fashion. In addition, depth discrimination can be substantially improved, in agreement with theory.