| 摘要 |
<p>A cross-field velocity filter for separating ions having a predetermined velocity comprises a pair of electrodes (11, 12) for producing a radial electric field and a pair of pole pieces (13, 14) for producing a magnetic field which crosses the electric field so that the crossed-field velocity filter has the same focusing properties for an ion beam in both the direction of the electric field and the direction of the magnetic field.</p> |
