Patent ID: 6844678
Filing Date: 2005-01-18
Classification: G03F,H01J

Abstract:
1. Short arc discharge lamp comprising: an essentially spherical arc tube; a cathode and an anode disposed opposite one another within the arc tube; wherein the cathode is composed of a plurality of particles which contain an emissive material, wherein said particles are larger in a cathode tip area than in a rear cathode area, and wherein the emissive material contained in the cathode tip area is present in a proportion of equal to or less than 0.1% by mass relative to the mass of the cathode tip area; and wherein the particles in the cathode tip area have an average particle size of from about 0.25 to 0.75 mm and the particles in the rear area have an average particle size of from about 0.02 to 0.1 mm.