| 摘要 |
PROBLEM TO BE SOLVED: To prevent a connecting part of electrode pins and a metal foil from getting abnormally high in temperature, and further to prevent cracks from occurring in a constituent material of an envelope in the vicinity of such a connecting part, even during a heat cycle due to repetition of lighting-on and -off. SOLUTION: In the high-pressure discharge lamp, foil-like coating members 9 formed in a cylindrical shape closely cover at least a portion of the electrode pins 5b positioned at a sealing part 4. Each coating member 9 has an opening face 11 formed including a portion of virtual line L passing the connecting part 10 of the metal foil 7 and the electrode pin 5b in parallel with the center line in longitudinal direction of the electrode pin 5b. Out of the coating members 9, on a cross section cutting a region including the opening face 11 with a face vertically crossing the virtual line L provided, when a center angle of a circular arc of the opening part is a°, a relation of: 5≤a<180 is satisfied, and on the cross section, a middle point of the circular arc is nearly positioned on the virtual line L. Moreover, the electrode pin 5b is in contact with the constituent material of the envelope 2 through the opening face 11. COPYRIGHT: (C)2010,JPO&INPIT
|
