Ultra-High Frequency and Small Aperture Size Circular Array Based on Piezoelectric Polymer for Intravascular Ultrasound Imaging

This work presents a novel approach for fabricating circular arrays for intravascular ultrasound (IVUS) imaging, successfully achieving a 32-element, 55 MHz transducer with a compact 1.5 mm aperture size, based on piezoelectric polymer. The innovative use of PVDF-TrFE (polyvinylidene fluoride-trifluoroethylene) as the piezoelectric material enables high bandwidth (80%) and minimal crosstalk (< −60 dB). Radial imaging tests were conducted using needles (D = 0.8 mm). The synthetic aperture method produced an image with a 2 mm penetration depth and an estimated a radial −6 dB beamwidth of 30 μm. The circular array provides a promising solution to the challenges of system complexity in high-frequency IVUS imaging.