Electron gun with specific grid electrodes

摘要

An electron gun for a cathode ray tube includes a triode portion composed of a cathode, a first grid electrode and a second grid electrode. Each of the first and second grid electrodes has beam-guide holes. The beam-guide hole of the first grid electrode is larger than the beam-guide hole of the second grid electrode. The hole portion of the first grid electrode is thinner than the hole portion of the second grid electrode. The distance between the first grid electrode and the second grid electrode is two or three times greater than as the distance between the cathode and the first grid electrode.