| 摘要 |
PROBLEM TO BE SOLVED: To provide a coil filament having stable luminescent properties and stable reliability by constituting a uniform winding pitch over the entire length of a winding part, and to provide an incandescent lamp using the same.SOLUTION: A coil filament 3 formed of a tungsten parallel element wire 1 is fabricated in such a manner that: around the parallel element wire 1 formed by bringing two tungsten wire members 1a, 1b in contact with each other in parallel, a molybdenum winding wire member 10 is spirally wound to form a string of original wire 11; the original wire 11 is then spirally wound to be formed into a coil filament shape 14; and thereafter, the molybdenum winding wire member 10 is molten by using mixed acid and is removed.SELECTED DRAWING: Figure 3 |
