| 摘要 |
PURPOSE:To obtain a discharge lamp with stable arcing, a uniform luminous distribution along the axis of a luminescent tube, and a high efficiency by specifying the ratio of the maximum inner diameter of a luminescent tube to the distance between the electrodes. CONSTITUTION:When the maximum inner diameter of a luminescent tube 1 is expressed as Dmm., and the distance between the electrodes as lmm., l/D is specified to be <=2.5. With this luminescent tube 1 enclosed in a vacuum external tube, when the lamp is lit up with an electrode 2 downward, the melted additional materials make a reservoir 6 in the lower end section of the luminescent tube 1, and the liquefied additional materials are shifted to the high temperature section of the electrode 2 for vaporization. At this time, an arc 7 is linear and stable and the luminous distribution in the axial direction of the tube is uniform. |
