| 摘要 |
PURPOSE:To obtain a good characteristic of low temperature start of a lamp, by providing spare electrodes having a distance from each other smaller than that for regular electrodes. CONSTITUTION:A transparent conductive film 9 is formed on the inner face of a glass tube 1, and lead wires 10 for spare filaments are embedded to stems 3 separately from lead wires 4. Spare filaments 11 are supported at positions of ends of the lead wires 10 and toward the direction nearer to center of the tube from regular filaments 5. Common pins 12 and regular filament pins 13 that are connected to one of the lead wires 4 of the regular filaments 5 and spare filament pins 14 are taken out from outside end parts of the tube. |
