Patent ID: 6774559
Filing Date: 2004-08-10
Classification: H01J

Abstract:
A metal vapor discharge lamp comprising:an outer tube having a closed portion at a first end and a base at a second end; a discharge tube inside of which an electrode is provided, located in the outer tube; and a sleeve enveloping the discharge tube and located in the outer tube, wherein; the sleeve comprises an open portion on the closed portion side of the outer tube, the closed portion side of the outer tube is provided with a support for supporting an end of the closed portion side of the sleeve, the support comprises a column portion having a narrow plate shape or a narrow stick shape separated from the open portion of the closed portion side of the sleeve, and a sleeve holding portion provided at an end of the column portion and is in contact with the sleeve, the support is connected to a feeding body connected to the electrode and led from the discharge tube toward the side of the closed portion, and connected to an electric power supply wire extending toward the side of the base, the column portion and the sleeve holding portion are formed of one continuous member, and the following relationship is satisfied: 0.05R&lE;W&lE;0.25R wherein W (mm) denotes a width of the column portion having the narrow plate shape and R (mm) denotes a maximum outer diameter of the outer tube.