| 摘要 |
PURPOSE:To obtain a double tube type lamp, in which the distance between electrodes is long despite its dimensions and which is easily manufactured, by fixing an inner bulb to the flare a steam by fusion or adhesion. CONSTITUTION:After an exhaust tube 7 and two electrode lead wires 8 are inserted in a glass tube 4 having a flare 9, one end of the glass tube 4 is heated and sealed. Next, an inner bulb 12 is directly fixed by fusion or adhesion to a part of the flare 9 which is located between a plural number of anodic lead wires 5 and 6 and the glass tube 4 of a steam, which is constituted by fusing the anodic lead wires 5 and 6 to the above flare 9. After that, the inner bulb 12 is sealed in an outer bulb 11 by fusion according to the convertional method, thereby completing assembly of a double tube structured lamp. By the means mentioned above, work of the lamp is remarkably facilitated, and the shift between the center axes of the inner and the outer tubes which may become a problem in a lamp of this type is greatly reduced. Consequently, an emissional polarization and the like can be almost prevented. Besides, owing to the increased distance between the electrodes, a high luminous output is realized despite the small size of the lamp, and the luminous efficiency is enhanced. |
