Low-pressure ultraviolet emitter utilizing chlorine and krypton chloride molecules

Abstract

Results are given of an investigation of the electrical and optical characteristics of the plasma of a longitudinal high-frequency discharge in a krypton/chlorine mixture (P ≤ 1000 Pa). The high-frequency discharge is ignited in a cylindrical quartz tube with an inside diameter of 14 mm and a distance between the anode and cathode of 30 mm. The dynamics of current and radiation of the high-frequency discharge utilizing krypton/chlorine mixtures of different compositions and pressures are investigated. It is found that a longitudinal high-frequency in a krypton/chlorine mixture is a broadband excimer-halogen emitter in the 200–260 nm spectral range. The ultraviolet spectrum of the lamp is formed as a result of overlapping of broadened radiation bands of chlorine and krypton chloride molecules (200 nm ^**₂ , 222 nm KrCl, and 257 nm Cl ^*₂ ). The optimal composition of a Kr/Cl₂ mixture is determined, which is necessary to obtain the maximal power of ultraviolet radiation.