| 摘要 |
<p>PROBLEM TO BE SOLVED: To reduce variations in the amount of electron emission by keeping a gap between electrodes constant. SOLUTION: A cathode electrode 3 made of conductive material is formed in stripes on an insulating cathode substrate 2, a film-like emitter layer 4 made of conductive material having substantially the same width as the cathode electrode 3 is formed in stripes on the cathode electrode 3, glass beads 5 acting as insulating support members are fixed on both sides of the emitter layer 4 on the cathode substrate 2, and a film-like gate electrode 7 having porous portions is formed on surfaces of the glass beads 5. The distance between the cathode electrode 3 and the gate electrode 7 is defined by the diameter of the glass beads 5, and thus the gap between them is kept constant.</p> |
