Patent ID: 8471473

Claim:
A discharge lamp device, comprising: an arc tube, including a sealed glass chamber in which at least a metallic halide and a rare gas are sealed by pinch-sealing both end openings of a glass tube; and electrode bars of tungsten provided opposite each other; wherein the longitudinal cross sectional crystal structure of the tip of a region projecting into the sealed glass chamber of each of the electrode bars is formed of a single crystal structure, wherein the longitudinal cross sectional crystal structure of the area other than the tip formed of the single crystal in the electrode bar tip side region projecting into the sealed glass chamber comprises a non-sagging crystal structure having a plurality of stacked slender crystals extending along an axial direction; wherein each of said electrode bars comprises an electrode bar mainly composed of a potassium-doped tungsten, the arc tube is installed in the discharge lamp device after the electrode bar has been vacuum heat-treated within a range of 1200° C. to 2000° C., and subjected to aging processing of repeating ON/OFF of the arc tube after the arc tube has been assembled.