| 摘要 |
In a field emission device, the fundamental cause of spherical aberration in an emitted electron beam trajectory is eliminated or mitigated. An aberration suppressor electrode 31 is provided at a lower vertical position than an extraction gate electrode 13 so its opening inner peripheral edge 31e faces a position near an emitter tip 11tp. The vertical position of the opening inner peripheral edge 31e of the aberration suppressor electrode 31 is made lower than the vertical position of the emitter tip 11tp. An aberration suppressing voltage Vsp is applied to the aberration suppressor electrode 31 that is a lower voltage than the potential of the emitter 11 and controls equipotential lines near the emitter tip 11tp to make them parallel. |
