Transparent ultrasound transducer based on PZN-PT single crystal for ultrasound/photoacousitc image

Photoacoustic imaging (PAI) plays an important role in biomedical imaging technology, which combines high optical contrast and deep penetration of ultrasound. To overcome the block of light path by conventional opaque transducers, transparent ultrasound transducer (TUT) was introduced for PAI to allow light transmitting through the transducer directly. Nevertheless, the sensitivity of TUT was generally limited due to limited transparent matching layer and low piezoelectric properties of transparent active layer, especially lithium niobate (LN) single crystal. Although efforts have been paid on developing novel transparent composites matching layer, few work investigate the high-performance transparent piezoelectric material for the active layer of TUTs. In this study, we propose to employ Pb(Zn1/3Nb2/3)O-3-PbTiO3 (PZN-PT) single crystal for TUT application, to improve sensitivity. A 20 MHz TUT was developed with > 50 % bandwidth and -23.9 dB insertion loss. Ultrasound in vivo imaging was achieved based on the TUT. In addition, the combined ultrasound/photoacoustic imaging performance of the PZN-PT based TUT was evaluated by imaging of ex vivo phantom.