Abstract

A piezoelectric detection system consisting of concentric rings is investigated for large depth of field photoacoustic imaging. Compared to a single ring, the array with its dynamic focusing capability leads to a reduction of imaging artifacts. Image resolution studies are performed in simulations and in experiments. Detector arrays with four and eight rings were simulated to compare axial and lateral resolution. In simulation an improvement regarding the reduction of X-shaped imaging artifacts for the eight ring detection system in comparison to a four ring detection is presented. To compare the resolution axial and lateral profiles are shown and discussed. Furthermore signal processing methods are demonstrated, such as coherence factor weighting, which improve resolution and further reduce artifacts. To demonstrate the multiple ring detection system in experiment we used a 4 ring detection system and crossed horse hairs as phantom. Different projection images and a 3D image of the phantom are presented.

© 2011 OSA/SPIE