ELECTRODE FOR SHORT ARC TYPE DISCHARGE LAMP AND SHORT ARC TYPE DISCHARGE LAMP

摘要

PROBLEM TO BE SOLVED: To provide an electrode for a short arc type discharge lamp and the short arc type discharge lamp exhibiting long life whereby wear of the electrode is reduced, deterioration of illuminance maintaining ratio of the discharge lamp is restrained, light emission efficiency is enhanced and illuminance stability is excellent.;SOLUTION: The electrode is constituted by a negative electrode 2 and a positive electrode 3 oppositely arranged in an arc tube 1 wherein mercury and a rear gas are sealed. The negative electrode 2 is formed by doping thorium dioxide on a high fusing point metal, and a thorium dioxide removed layer 2a is formed on a top most surface of the negative electrode 2 to a predetermined depth.;COPYRIGHT: (C)2003,JPO