| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a lighting device prevented from lighting failure caused by a crack formed in a thin tube to leak a light tube, while a preferred color property is maintained. <P>SOLUTION: In the lighting control metal halide lamp having a pair of electrode 21 placed in the lamp, filled with a metal halide, provided with a lighting tube 5 having a surroundings 19 comprising a transparent ceramics, the metal halide comprises at least a kind of the rare earth metal halide consisting of dysprosium halide, holmium halide, thulium halide, holmium halide, cerium halide, and praseodymium halide, and sodium halide, together with at least a magnesium halide consisting of magnesium iodide and magnesium bromide, wherein the relations of A≥0.021p+0.313, and B≥10.0 in 0.0345A+0.0028B<0.00115p+0.0475 are satisfied when the total amount of metal halides filled is A, and the ratio of magnesium halide filled and the metal halide is B(mole%) when maximum lamp power P(W) being in the range of 70W to 250W. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
