| 摘要 |
<p>The handpiece for driving a surgical instrument comprises a magnetic field source 23 positioned to apply a magnetic field to the surgical instrument and a magnetic field sensor 4. There may be more than one source and more than one sensor. In use the magnetic field generated by the source is measured by the sensor and this is deflected by soft magnetic material 12 on the instrument 10. A property of the instrument is then determined based upon the shape of the magnetic material.</p> |
