Image restoration and wave-field error removal in holographic acoustic microscopy

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