| 摘要 |
PROBLEM TO BE SOLVED: To provide satiofactory luminous efficiency in a luminaire having a sealed structure and improve the rising characteristic of luminous flux. SOLUTION: This fluorescent lamp has a lamp power rating of 10-110 W and has a structure where a phosphor layer 2 is formed on the inside surface side of an elongate translucent discharge container 1, having a tube diameter of 15-38 mm and a tube length of 300-2,400 mm, a pair of electrodes 3 are enclosed at both its ends, a main amalgam 6 having a mercury vapor pressure control action is fixed at least at one of the ends, an auxiliary amalgam 7 is disposed in the vicinity of the electrode, at least part of which is enclosed at the end part on the side where the amalgam 6 of the translucent discharge container 1 is present, and the mercury vapor pressure is controlled by the coolest part such as a fluorescent lamp filled with pure mercury when ambient temperature is 20 deg.C or lower. When the ambient temperature is 25 deg.C or higher, the mercury vapor pressure is controlled by the main amalgam 6. Gold is used as a constituent metal of the auxiliary amalgam.
|
