Prototype 3D Real-Time Imaging System Based on a Sparse PZT Spiral Array

3D ultrasound imaging is costly and complicated mostly due to the need of controlling 2D probes with high numbers of elements (≥1024). Sparse arrays are a convenient way to reduce system complexity maintaining reasonable performance. A 256-element density tapered spiral array has been recently designed and realized in a piezoelectric probe prototype. The probe has been connected to the ULA-OP 256 open scanner, which can be programmed to permit volumetric scanning in real-time. This paper reports on the first experimental measurements of transmit ultrasound fields produced by such prototype system, including multi-line transmit fields that, in combination with parallel receive beamforming, may permit real-time volumetric imaging. An average -21.3dB side-lobe level (SLL) was measured on the transmit fields, while volume rates of 35 volumes per second can be achieved.