Recent results from dual-layer array transducers for 3-D imaging

The difficulties associated with fabricating and connecting 2-D arrays with large numbers of elements have limited the development of arrays with more than 5000 elements. In order to simplify transducer design and system requirements, we proposed a 5 MHz PZT-P[VDF-TrFE] dual layer transducer array design before which used perpendicular 1-D arrays for 3-D imaging of targets near the transducer. This transducer design reduces the fabrication complexity and the channel count. As higher frequencies (>;5 MHz) are more commonly used clinically, in this paper, we present an 8 MHz planar dual-layer transducer array for 3-D rectilinear imaging. Meanwhile, regarding the clinical needs for 3-D transrectal ultrasound (TRUS), we also present a 5 MHz cylindrical dual layer transducer array here, which would be used for visualizing the prostate, guidance of biopsies, and monitoring therapeutic procedures. The flexibility of the copolymer material used in dual-layer scheme also makes it easy to mold around a cylindrical form. Performance of both arrays is verified through simulations and experiments.