| 摘要 |
PURPOSE:To provide a fluorescent lamp that prevents a slightly opaque phenomenon generated on the inner surface of an outside tube near an electrode and will not damage workability when an inside tube is manufactured. CONSTITUTION:Two U-shaped inside tubes 4a and 4b made of silicate glass whose sodium component is approximately 3 to 10% through a holder 5 adhering to a stem 2 in the airtight space comprised with an outside tube 1 and the stem 2 and coated with phosphor 3 on an inner surface and a series of discharge paths are comprised with the inside tubes 4a and 4b and a connection path provided at the holder 5 are formed. A pair of electrodes 7a and 7b are arranged on both ends of the discharge paths and the opening end of one inside tube 4a is opposed to one electrode 7a and then the electrode 7a is comprised as the negative electrode. As a result, since there is no inside tube 4a around the electrode 7a, a sodium component is prevented from being diffused from the inside tube near both electrodes and a slightly opaque phenomenon can be eliminated. |
