| 摘要 |
<p>PURPOSE:To cope with a short circuit between gates and an emitter tip, and to carry out versatile control of emitting electrons, as to a field emission cathode. CONSTITUTION:An emitter tip 1 with a sharp tip, and plural gate electrodes 21 to 24 provided around the tip of the emitter tip 1 are provided, and the voltage can be applied to the plural gate electrodes independently respectively. The above plural gate electrodes are arranged at the point symmetry making the tip of the above emitter tip as the center, and the gate electrodes at the symmetric positions are connected in the same potential. To the above plural gate electrodes, the power is to be fed through an over-current cut-off element 8.</p> |
