| 摘要 |
PROBLEM TO BE SOLVED: To provide an incandescent lamp which does not cause discharge between a luminescent part of a filament and an internal lead rod, even if a gas filling pressure is low, as for an incandescent lamp of a sealed end type with a rated voltage of 12 V. SOLUTION: In an incandescent lamp with a rated voltage of 12 V, in which a valve 10 having a sealing part 11 and the remainder of an exhaust tube 12, a filament 20 with a luminescent part 23, the first internal lead rod 30 and the second internal lead rod 40 are equipped, a gas filling pressure in the glass bulb 10 in which rare gas is filled is set for 5×10<4> -1×10<5> Pa (25 deg.C), a length L of the first lead rod 30 existing in a space from an inner end of the sealing part 11 to an end surface on the sealing part side of the luminous part 23 is set for 3.0-8.0 mm, and the shortest distance between an end part 231 of the luminous part 23 and the first internal lead rod 30 is set for not less than 0.30×L (mm).
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