| 摘要 |
<p>The present invention relates to a device assembly and tissue ablation transducer (400) having a plurality of helical elements that can be operated out of phase to orient the acoustical energy beam forward or backward in the longitudinal direction. The transducers includes a cylindrical inner electrode (402), a cylindrical piezoelectric (403) material disposed over the inner electrode, and a cylindrical outer electrode (404) disposed over the cylindrical piezoelectric material. Spiral grooves (figure 4a) are cut through at least the outer electrode separating the transducer into a plurality of functionally discrete helical transducer segments. The helical transducer segments can be operated independent from one another. An array of intertwined helical transducers arranged linearly along a helical axis are also contemplated.</p> |
