METAL VAPOR DISCHARGE LAMP AND LIGHTING APPARATUS THEREFOR AND PROJECTION APPARATUS USING THEREOF

摘要

PURPOSE: To prevent degradation of light transmissive function of a light emitting tube and prevent temperature rise by preventing occurrence of devitrification and sublimation in an insulating sleeve formed on an electrode shaft. CONSTITUTION: A metal vapor discharge lamp is provided with a bulb 2 made of quartz glass, a pair of electrodes 4 sealed in the bulb 2, an insulating sleeve 9 formed on the base parts 5 of these electrodes 4, and layers 90, 95 consisting of a nitrogen component and formed on the surface of tip part including at least the tip face of the insulating sleeve. Since the layer consisting of a nitrogen component is formed on the insulating sleeve, the surface of the insulating sleeve becomes hard to be recrystallized and heat resistance is improved and devitrification and sublimation are prevented.