High frequency ultrasound arrays for medical imaging

30 MHz composite linear arrays with 48 elements were designed, fabricated, and tested. Bandwidths of 60%, low crosstalk and insertion loss, and electrical impedance matching to 50 ohms were achieved. Images of a phantom and a human eye were acquired, with the phantom image demonstrating lateral and axial resolutions of 100 microns. A simpler, non-composite array incorporating lead-titanate elements was also fabricated. Test results demonstrated that the more complicated composite design is superior, a result attributed primarily to the low permittivity of the lead-titanate elements.