Patent ID: 6262535
Filing Date: 2001-07-17
Classification: H01J

Abstract:
High pressure discharge lamp (1) comprising:a lamp bulb (2) of quartz glass, and defining a lamp axis;two electrode necks (4, 4a, 4b) projecting from said lamp bulb in alignment with said axis;two electrodes (11) each having a holding rod (10) attached thereto, said electrode rods extending into respective electrode necks; anda support tube (5, 20, 25) surrounding at least one of said holding rods (10) and located adjacent an inner region of the respective electrode neck,wherein, said support tube (5, 20, 25) has a generally conical outer surface which tapers in a narrowing direction towards the respective electrode (11),wherein the outer diameter of an inner end of said support tube is smaller than the outer diameter of the outer end of said support tube; andwherein the support tube is melt-connected with the respective electrode neck (4, 4a, 4b); andwherein a transition region (6) of the neck (4, 4a, 4b) and the bulb (2) is devoid of the support tube (5, 20, 25) to form a recess between the inner end of the support tube and an end portion of the bulb.