Alkali metal dispenser

摘要

An alkali metal dispenser in an electron tube for vapor depositing alkali metals on photoemissive surface within the tube envelope comprises a non-welded-tubular housing having walls formed by spirally rolling upon itself a thin sheet of tantalum so that the walls spirally overlap, preferably twice. The "double wrapped" dispenser prevents uncontrollable escape of alkali particles contained within the interior of the tubular housing and provides a substantially uniform orifice for repeatable release of alkali vapors.