Patent ID: 6534918
Filing Date: 2003-03-18
Classification: H01J

Abstract:
A high-pressure gas discharge lamp comprising:a lamp vessel which is closed in vacuumtight manner and has a quartz glass wall enclosing a discharge space; metal foils embedded in the wall of the lamp vessel, each connected to a respective external current conductor; electrode rods each connected to a respective one of said metal foils and projecting from the wall of the lamp vessel into the discharge space; an ionizable filling in the discharge space; the lamp being defined by the following relation, finw>=40% â€ƒin which: finw=fraction of length of the electrode rod enclosed in the wall of the lamp vessel, wherein the electrode rods have first and second discrete parts electrically connected together at facing ends, said first parts projecting into the discharge space and are a first material, said first material consisting essentially of tungsten, said second parts are enclosed in the wall and are a second material, said second material being different from the first material and comprising rhenium, each of said electrode rods changing at said facing ends from the first material to the second material.