To reduce and prevent electrode displacement and at the same time to devise an
arrangement of the side tube parts with high adhesion, a short-arc, ultra-high
pressure discharge lamp a light emmitting part in which there is a pair of opposed
electrodes and which is filled with at least 0.15 mg/mm3 of mercury
is provided with side tube parts which extend from opposite sides of the light
emitting part in which the electrodes are partially hermeticallly sealed and in
which the electrodes are each welded in a central valley of a metal foil that has
a cross section with an essentially inverted W-shape. The valley and flanking arches
or peaks of the W-shape may be sarpentine or sinusoidal, trapezoidal, or rectangular
in addition to the traditional W-shape having acutely angled corners between straight legs.
