| 摘要 |
<p>A handpiece (10) having two sets of piezoelectric elements (18, 20). One set of elements (20) is polarized to produce longitudinal motion. The other set of elements (18) is polarized to produce torsional motion. An appropriate ultrasound driver drives each set of elements at their respective resonant frequencies to produce longitudinal vibration and torsional oscillation.</p> |
