HID LAMP

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Disclosed is an HID lamp that can suppress a chemical reaction between a rare earth metal, which is sealed in an electric discharge container, and an electrode and consequently can significantly improve the service life of the lamp. A coil (10) for cooling is wound around the front end of the electrodes (7b, 8b).? A coil (11) for cooling is wound around a part from the middle part to a welded part of the electrodes (7b, 8b).? Further, the gap between the coil (11) and the electrodes (7b, 8b) is filled with Dy2O3 as an oxide of a rare earth metal constituting a compound (metal halide) of a rare earth metal sealed in the electric discharge container and a halogen.? Thus, since Dy2O3 is filled in this way, vapor of the rare earth metal does not reach the stopper (7a, 8a) of Nb and, thus, any substitution reaction does not occur.