| 摘要 |
PROBLEM TO BE SOLVED: To attain such incompatible effects as high color rendering property (Ra≥80) and high efficiency (η≥100(lm/W)) in a metal halide lamp. SOLUTION: A translucent ceramics arc tube 1 is designed to continuously form capillaries 3A, 3B on long-axis-direction both sides of a light emitting part 2 formed into an almost ellipsoidal shape via a corner-less transition curved surface 4 to set the effective length L/effective inner diameter D to 1.8-2.2 and is formed to have a size that a minimum temperature of the light emitting part is at least 800°C and a maximum temperature of the light emitting part is not more than 1,200°C when turned-on. As metal halides, at least thulium iodide, thallium iodide, sodium iodide and calcium iodide are filled and the sodium iodide and the calcium iodide are filled at molar ratios of 40-80% or less and 30% or less relative to all of the metal halides. COPYRIGHT: (C)2011,JPO&INPIT |
