Metal vapor discharge lamp

摘要

A metal vapor discharge lamp including an outer tube 1 having a closed portion 1a at a first end and a base 2 at a second end; a discharge tube 3 inside of which an electrode is provided, located in the outer tube 1; and a sleeve 4 enveloping the discharge tube 3 and located in the outer tube 1, wherein the sleeve includes an open portion on the closed portion 1a side of the outer tube 1; the closed portion 1a side of the outer tube 1 is provided with a support 8 for supporting an end of the closed portion 1a side of the sleeve; the support comprises a column portion 10 having a narrow plate shape or a narrow stick shape separated from the open portion of the closed portion 1a side of the sleeve, and a sleeve holding portion 11a provided at an end of the column portion 10 and is in contact with the sleeve 4; and the support 8 is connected to a feeding body 6a connected to the electrode and led from the discharge tube 3 toward the side of the closed portion 1a, and the support 8 also is connected to an electric power supply wire 15 extending toward the side of the base 2. Thereby, it is possible to provide a high efficiency and long lifetime metal vapor discharge lamp capable of suppressing abnormal noises after the lamp is turned on or off with the sleeve supported firmly.