| 摘要 |
<p>PURPOSE:To enable to start or stop electron emission quickly and exactly, by mounting the first and the second electrodes respectively on the forward and backward sides of electron-emitting elements and applying voltages to these electrodes to make the elements emit electrons, while the first electrode is ring-shaped and divided into the plural number of pieces to apply an independent voltage to each of them. CONSTITUTION:An insulating film 6 is formed on a substrate 2 of glass or the like, and then a p-type semiconductor layer 8 and a n-type semiconductor layer 10 are laminated thereon. In the central part of the layers, an inverse cone-shaped hole 11 is bored to form a lower electrode 4 on the exposed surface of the substrate 2. Successively, the layers 8 and 10 facing the hole 11 are changed to p<+> and n<+> types, and then the surface of the layer 10 is covered with an insulating layer 14, whereon upper electrodes are formed approximately in a ring shape and divided into electrodes 16-1 to 16-4. The layers 8 and 10 are then connected with a source 12 for application of inversely biased voltage, and individual sources 20-1 to 20-4 are connected between the electrodes 16-1 to 16-4 and the layer 10 respectively. Thus, electron emission is exactly started/ stopped and the energy is effectively controlled.</p> |
