Vacuum ultraviolet rare gas excimer light source

A dc electron beam at 20 keV is used for the excitation of pure rare gases at pressures up to 1.7 bar. The well known second excimer continua of argon, krypton, and xenon observed under these excitation conditions provide an efficient light source in the vacuum ultraviolet spectral region between 120 and 200 nm. Thin (300 nm) SiNx foils are used as entrance windows for the low energy electron beam. Due to the flexibility of the production process of the thin foils one can consider various shapes and sizes of the light emitting region to be manufactured. Efficiencies of ∼30% are observed for the conversion of electron beam energy into light.