A preform of a fluorine central lamp, with such a preform produced fluorine or a combination of the lamp and production method

摘要

PROBLEM TO BE SOLVED: To prevent the breakage of a structure having no exhaust tube, accelerate the evaporation of mercury existing near a filament, and quickly stabilize the characteristic by providing a proper interval between the inner diameter of a bulb and the outer diameter of a stem, conducting the exhaust and filling of an inert gas through this interval, then sealing the bulb. ;SOLUTION: In this fluorescent lamp 1 for indicator light, a discharge chamber 4 is formed with a bulb 2 coated with phosphors 2a on the inner face and a stem 3, and a filament 5 coated with an electron emissive material 5a and a discharged electrode 6 are fitted to the stem 3. An inert gas 7 such as argon, neon, krypton, or xenon and a proper quantity of mercury 8 are filled in the discharge chamber 4. The inner diameter of the bulb 2 is made properly larger than the outer diameter of the stem 3 to form a proper interval between them when the stem 3 is inserted into the bulb 2. The stem 3 is inserted into the bulb 2, the exhaust and the filling and sealing of the inert gas 7 are conducted through the interval, and no exhaust tube is required.;COPYRIGHT: (C)1998,JPO