High-pressure gas discharge lamp having electrode rods with crack-initiating means

摘要

A high-pressure gas discharge lamp has a bulb of quartz glass and two electrode rods. One end of each electrode rod is connected to a molybdenum foil member embedded in the quartz glass material, while the other end of each electrode rod projects into the gas discharge space inside the bulb. A portion of the electrode rod is embedded in the quartz glass material of the bulb. The surface of said embedded portion of the electrode rod is provided with means dots, recesses and/or protrusions for initiating cracks at predetermined locations in the quartz glass material surrounding the electrode rod during manufacture of the lamp.