Measurement of Ba atom emission from fluorescent lamp electrode using laser-induced fluorescence

Abstract

A laser-induced fluorescence technique was applied to make measurements of temporal and spatial distributions of Ba atoms in the vicinity of the electrode of a fluorescent lamp operated at DC and AC 60 Hz. Ground state Ba atoms were excited to an upper level by an UV laser beam, then the subsequent fluorescence was detected. Ba atoms are emitted mainly from the hot spot of the filament electrode. It is suggested that the main factor of Ba atoms emission from the electrode is due to not an ion bombardment but a thermal evaporation.