SHORT ARC TYPE METAL HALIDE DISCHARGE LAMP, METAL HALIDE DISCHARGE LAMP DEVICE, AND LIGHTING APPARATUS

摘要

PROBLEM TO BE SOLVED: To provide a short arc type metal halide discharge lamp having slow corrosion rate properties of molybdenum foil at the sealing portion, without using mercury that has heavy environmental load and poor light starting characteristics. ;SOLUTION: In the lamp, there are provided an airtight vessel 1, an electrode 2 with its sealing portion mirror surface finished by electrolytic polishing, a molybdenum foil 3, and outer lead-wire 4. The airtight vessel 1 is molded in the form of rotating ellipse face having outer diameter of 7 mm out of quartz glass. The airtight vessel 1 is integrally provided with a pair of elongated seal closures 1a extended from both longitudinal ends of the ellipse. Within the airtight vessel 1, an inert gas, a first halide and a second halide are filled as discharge medium. As the inert gas, 5 atm of xenon is used. As the first halide, 3.5 mg of sodium iodide and 0.5 mg of scandium iodide are used. As the second halide, 0.6 mg of ZnI2 is used.;COPYRIGHT: (C)2001,JPO