US Patent 8253332 Excimer lamp

An excimer lamp has a single tubular discharge chamber configured to enclose a discharge gas that is a noble gas or a mixing gas consisting of a noble gas and a halogen gas; a pair of electrodes configured to be arranged along opposite sides of the exterior surface of the discharge chamber; and an outer tube configured to cover the discharge chamber and the electrodes. Excimer molecules are produced by either dielectric barrier discharge or capacitive-coupled high-frequency discharge. An interior of a space formed between the outer tube and the discharge chamber is either in a vacuum state that is necessary and sufficient for preventing discharge, or is filled with an arc-suppression gas.