Low-artifact and long depth of field photoacoustic microscopy using a Gaussian- weighted annular array

摘要

A Gaussian-weighted annular ultrasound array is proposed to reduce artifacts and extend the depth of field of acoustical-resolution photoacoustic microscopy. By applying Gaussian weighting on each ring, the annular array suppresses the side lobes by about 18 dB compared to a conventional focused transducer, and "X"-shaped artifacts are significantly reduced in the photoacoustic images. Additionally, by controlling the delay time of each ring, the annular array can dynamically focus at different depths, thus achieving a long depth of field. Experiments are performed which demonstrate that the proposed scheme can significantly improve the imaging quality of photoacoustic microscopy. (c) 2019 The Japan Society of Applied Physics