摘要 |
A short-arc type discharge lamp includes a cathode and an anode which are arranged opposite to each other in a light emitting tube, wherein the cathode contains a light rare earth oxide as an emitter substance. When the cathode is composed of a body part, which comprises tungsten containing the light rare earth oxide as an emitter substance, and a tip part, which comprises tungsten bonded to the tip side of the body part, excessive evaporation of the light rare earth oxide as an emitter substance from the cathode and early exhaustion caused by the same can be prevented. An aspect ratio of tungsten particles in the body part of the cathode is greater than the aspect ratio of the tungsten particles in the tip part thereof. |