| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a discharge lamp (10) which improves the stability of its attachment to a lamp holder and stabilizes the intensity of its outgoing light. <P>SOLUTION: The discharge lamp (10) has a fastening mouthpiece (20) at its one end which is inserted into a lamp holder (50) having a reference surface (54). The fastening mouthpiece has a first barrel portion (21) having a pair of first notch portions (21H) formed on the outer periphery of a cylinder which is at the end of the lamp, a second barrel portion (23) having a pair of second notch portions (23H) formed on the outer periphery of the cylinder which functions also as a joining portion of the lamp, and a groove portion (25) formed along the outer periphery of the cylinder between the first and second barrel portions whose diameter is not larger than the space between the pair of first notch portions. The space between the pair of first notch portions is not larger than the space between the pair of second notch portions, and the diameter of the first barrel portion is not larger than the diameter of the second barrel portion, and further, an axial end surface (21B) of the groove portion which is formed on the side of the first barrel portion is so joined to the reference surface (54) as to be fastened to the lamp holder. <P>COPYRIGHT: (C)2009,JPO&INPIT |
