HEART: 2 D ARRAY TRANSDUCERS FOR MEDICAL DIAGNOSTIC ULTRASOUND

Pennsylvania State University-Univ Park, University Park PA

Investigators

Linked publications & trials

Abstract

The Duke group has been developing 2-D arrays for 3D intra-cardiac ultrasound imaging for many years. The 2D arrays are currently fabricated from PZT-5H. The purpose of this program was to assess the advantages of applying single crystal PZN/PT to an existing Duke design for an intravascular 2D array. The extremely high piezoelectric properties and low acoustic impedance of PZN/PT in 33 mode operation should allow significant improvements in range resolution and grating lobe amplitude as each element should operate over a much broader bandwidth. The drawback is the difficulty in fabrication of a device with such a new material, where many of the properties are either unknown to date or vary form batch to batch. This project has been undertaken on two fronts. The fabrication issues have been examined simultaneous with the modeling. Because of the single crystal nature of PZN/PT, one dimensional models could only provide a rough estimate of the transducer performance. For a more accurate simulation, FEA modeling has to be used. To do so, materials properties of the single crystals must be known. These material properties are still lacking. Future work in modeling includes more materials properties measurements and verification of crystal alignment controlled resonance modes.