Patent ID: 7973476

Claim:
A high pressure mercury discharge lamp that is provided for DC operation with a nominal power of higher than 1.5 kW, comprising a discharge vessel, an anode and a cathode that are arranged in the discharge vessel, the diameter of the anode being between 25 mm and 70 mm, and at least the anode being formed, at least in some areas, from a material that has at least a proportion of tungsten and a fill that is located inside the discharge vessel and contains mercury with a fill quantity of between 0.5 mg/cm 3 and 7 mg/cm 3 , as well as at least one inert gas with a cold fill pressure of higher than 0.8 bar, characterized in that the material of the anode has a grain number of greater than 200 grains per mm 2 and a density of higher than 19.05 g/cm 3 .