To devise an arrangement with relatively high pressure tightness, in a short-arc
super-high pressure mercury lamp which is operated with an extremely high mercury
vapor pressure, a light emitting part has a pair of opposed electrodes and is filled
with at least 0.15 mg/mm3 of mercury; and side tube parts extend from
opposite sides of the light emitting part, and in which the electrodes are partially
hermetically sealed and are each welded to a respective metal foil, in the areas
in which the electrodes are welded to the metal foils, the electrodes are deformed
in the direction perpendicular to the metal foils to a degree of deformation that
is at most 10%.