摘要 |
PROBLEM TO BE SOLVED: To provide a metal halide lamp capable of suppressing the deterioration of transmission when a protective film is formed and also capable of suppressing the deterioration of transmission caused by the discoloration and devitrification of the arc tube. SOLUTION: The metal halide lamp comprises an arc tube 11 filled with at least a metal halide and rare gas, a pair of electrodes 14a, 14b which are provided at both ends in the arc tube 11 and connected to external lead wires 13a, 13b, and a protective film 12 which is formed at a portion in the arc tube where the arc generated between the pair of electrodes 14a, 14b approaches. COPYRIGHT: (C)2006,JPO&NCIPI
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