| 摘要 |
PROBLEM TO BE SOLVED: To provide a luminaire having decontaminating and deodorizing effects by a larger photocatalyst action even in continuous lighting and requiring no maintenance such as its cleaning by storing an arc tube sealed with an inactive gas such as xenon, sodium, and mercury in it and having such an unsaturated vapor characteristic that nearly all of the sodium and mercury is evaporated while a lamp is lighted in an outer tube. SOLUTION: An arc tube 5 is arranged in an outer tube 1 made of quartz glass at the center section of the tube axis, and it is held in the outer tube 1 via a lead conductor. The arc tube 5 is made of a translucent alumina arc tube 6, it is sealed by ceramic caps 7a, 7b at both ends, and niobium electrode support tubes 9a, 9b fixing electrodes 8a, 8b at the tips are fixed to the center sections of the caps 7a, 7b through them. The prescribed quantities of xenon gas serving as an inactive gas, sodium, and mercury are sealed in the arc tube 5, and the sealed quantities of the sodium and mercury cause such an unsaturated characteristic that nearly all of them is evaporated while a lamp is lighted. |
