Low pressure discharge lamp having electrodes with a lithium-containing electrode emission material

Abstract

A low pressure discharge lamp in which, even during uninterrupted operation, a low lamp voltage characteristic is maintained over a long time interval and in which high radiant efficiency can be obtained over a long time is achieved via a low pressure discharge lamp which has a tubular glass bulb in which a pair of electrodes are located opposite one another, by an electron emission material which contains lithium being included on or in the electrode substrate. Advantageously, the electron emission material contains at least one of the following materials: metallic lithium, an alloy of lithium and another metal, an oxide of lithium, a mixture of an oxide of lithium with another metal oxide, and an oxide which contains lithium and another metal element and which is a compound identified by the formula Li--M--O.sub.x where M designates at least one element selected from among the alkali earth metals, rare earth metals and transition metal, and x is the number of oxygen atoms required for valency equalization.

Dependencies are inferred from the claim text.