| 摘要 |
PURPOSE:To prevent any damage to a cathode or the like from occurring even when electric discharge occurs in the tube by installing a high resistance between an anode and a bulb spacer contact. CONSTITUTION:An insulating layer 8 made of a ceramic material or similar material is packed into the drawn section of an anode 2a located near its opening. The insulating layer 8 has a piercing hole in its center. The diameter (D1) of the piercing hole and the diameter (D2) of the electron beam hole of the anode 2a are adjusted to satisfy formula D1>D2. When packing the insulating layer 8, a few bulb spacer contacts 7 and a high resistance 9 of several hundred ohms are buried. One of the bulb spacer contacts 7 and the high resistance 9 are electrically connected at contact 9a and the other bulb spacer contact 7 and the anode 2a are electrically connected at contact 9b. Anode voltage is supplied to the anode 2a through an interior conductive film 6, a bulb spacer contact 7 and the high resistance 9. |
