EFFICIENT XEI-ASTERISK EXCIMER ULTRAVIOLET SOURCES FROM A DIELECTRIC BARRIER DISCHARGE

A dielectric barrier discharge in mixtures of xenon and iodine to prov ide intense narrow band ultraviolet (UV) radiation at lambda = 253 nm (XeI) has been investigated. The characteristics of the emission spec tra of the excited dimer (excimer) and UV intensity formed from mixtur es of xenon and iodine for different total gas pressures are reported. The absolute UV output power of the XeI lamp has been determined usi ng actinometry based on the photohydrate of uridine. The electrical po wer dependence of the UV intensity generated as well as the conversion efficiency of the lamps has also been studied. Conversion efficiencie s (from input electrical to output optical energy) as high as 22.5% ha ve been achieved for an electrical power input of 70 W, with 15.75 W o f optical output being generated. (C) 1998 American Institute of Physi cs.