Multi-wavelength excimer ultraviolet sources from a mixture of krypton and iodine in a dielectric barrier discharge

Abstract

New ultraviolet (UV) sources (excimer lamps) have been demonstrated using mixtures of krypton and iodine in a high-pressure dielectric barrier discharge to provide intense multi-wavelength radiation at λ=183 nm (atomic iodine line, 4 P 5/2?2 P 3/2), 191 nm (KrI*, B 1/2?X 1/2), 206 nm (atomic iodine line, 2 P 3/2?2 P 1/2), and 342 nm (I* 2, D 1/2?X 1/2). The characteristics of the optical emission spectra of the atomic species and the excited dimers (excimers) formed for different total gas pressures and in the presence of a buffer gas have been investigated. The highest intensity, at 183 nm, is obtained at pressures up to 1 bar while the overall emission spectra can be controlled by adjusting the total pressure. The results show that these strong multi-wavelength lamps offer an interesting alternative to conventional UV sources.