Hg 185 nm and 254 nm resonance radiation production from a low pressure Hg-Ar discharge at high current densities

Abstract

Summary form only given. The power radiated by each of the 185 nm and 254 nm resonance lines of Hg as a fraction of input power per unit length to the positive column has been measured in a low pressure Hg-Ar discharge. Measurements were obtained over a range of current densities from approximately 0.05 A cm/sup -2/ to approximately 0.6 A cm/sup -2/. These measurements are thus relevant to a wide range of fluorescent lamp applications, from a 'standard' 32 Watt T8 fluorescent lamp (0.05 A cm/sup -2/) to the new generation of electrodeless fluorescent lamps, which operate at considerably higher current densities. Radiated power was determined by combining accurate measurements of the 6 /sup 1/P/sub 1/ and 6 /sup 3/P/sub 1/ resonance level populations with realistic Monte Carlo simulations of radiation transport/sup 2/. This method eliminates the need for direct UV/VUV radiometry, which requires a reliable 'standard of irradiance.' This and other problems are particularly acute at 185 nm. Resonance level populations were measured using high sensitivity absorption spectroscopy.