Miniature Transducer Using PNN-PZT-based Ceramic for Intravascular Ultrasound.

In this work, the development and performance evaluation of a high-frequency miniature ultrasonic transducer based on a Pb(Ni1/3Nb2/3)O3-Pb(Zr0.3Ti0.7)O3 (PNN-PZT-based) ceramic for intravascular imaging application are reported. The fabricated PNN-PZT-based ceramic possesses ultrahigh relative clamped dielectric permittivity (.S/.0 = 3409) and high electromechanical coupling capability (kt = 0.60). A 42-MHz high-frequency side-looking ultrasonic transducer probe using the PNN-PZT-based ceramic with a miniature aperture of 0.33 mm × 0.33 mm was designed and fabricated, which exhibited a wide -6 dB bandwidth of 79% and an insertion loss of -19.6 dB. High spatial resolution, including the axial resolution of 36 μm and lateral resolution of 141 μm, was determined by imaging a 13-μm tungsten wire phantom. Ex vivo intravascular ultrasound (IVUS) imaging of a porcine coronary artery was performed to show the imaging capability of the miniature transducer. The results demonstrated the great potential of PNN-PZT-based ceramic for high-resolution miniature transducers application.