| 摘要 |
PURPOSE:To shorten a supporting frame, and eliminate projection of the shadow of the supporting frame to provide uniform luminous intensity by directly connecting a final turn of a starting auxiliary body to a main electrode which does not have a heater of a luminescent tube. CONSTITUTION:A starting auxiliary body 41 comprising a 0.3phi molybdenum wire is wound on to the outer surface of a luminescent tube 1. Its one end is connected to a supporting frame 40 at the upper end of the luminescent tube 1 and the other end is connected to a lead 5b. Each of stem leads 7a-7c is passed through an outer tube 13 in airtightness. A glow starter 15 and a stabilizer 16 are accommodated into a case 30 which is integrated between the outer tube 13 and a base 8. By this construction, a supporting frame to be arranged along the luminescent tube 1 can be removed, and moreover, since the starting auxiliary body 41 is wound on to the outer surface of the luminescent tube 1 from its one end to the other end, shadows of the starting auxiliary body and supporting frame are not projected on the outer tube 13. Therefore, uniform luminous intensity can be obtained and decrease of luminous flux caused by shadow is prevented. |
