| 摘要 |
PURPOSE:To improve starting feature of a metal vapor discharge lamp as well as providing convenience of safe handling, by enclosing in a luminous tube a radioactive substance which is sealed dispersively in a material or its compound allowed to exist in the luminous tube, as a sealed radiation source. CONSTITUTION:Mercury as a buffer metal, metal halogenide, for example, scandium iodide or sodium iodide as a luminous metal, and krypton gas as rare gas for starting and the like are enclosed in a luminous tube 4. In the luminous tube 4, a sealed radiation source 15 of a radioactive substance is enclosed, and in the sealed radiation source 15, a radioactive substance 16 is sealed dispersively in its holding member 17. The holding member 17 is made of a luminous metal such as rare earth metal or the like, or oxide or halogenide of these metals which is enclosed in the luminous tube 4, or tungsten, molybdenum or their compound which makes electrodes 7, 8. Thereby, starting feature can be improved remarkably. |
