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An excimer lamp (or excilamp) is a source of ultraviolet light produced by spontaneous emission of excimer (exciplex) molecules.〔〔〔 == Introduction == Excimer lamps are quasimonochromatic light sources that can operate over a wide range of wavelengths in the ultraviolet (UV) and vacuum ultraviolet (VUV) spectral regions. The operation of excimer lamps is based on the formation of exci''ted'' dimers (excimers) and the following transition from the bound excited excimer state to a weakly bound ground state resulting to an UV-photon radiation. Maximum of an excimer lamp radiation wavelength is specified by a working excimer molecule (see table below). Wavelength and photon energy of excimer lamp radiation. Excimers are diatomic molecules or complexes of molecules that have stable excited electronic states and an unbound or weakly bound ground state. Originally only homonuclear dimers with a stable excited state but a repulsive ground state were called excimers (exci''ted'' dimers). The term excimer has since been extended to mean any multi-atom molecule with a thermally unstable (repulsive or only very weakly bonding) ground state. But sometimes one can meet term exciplex meaning an exci''ted'' complex. It is also excimer molecule but not homonuclear dimer. For example, Xe2 *, Kr2 *, Ar2 * are excimer molecules but XeCl *, KrCl *, XeBr *, ArCl *, Xe2Cl * are exciplex molecules. The best known include rare gas excimers and rare-gas-halogen excimers. Rare-gas-halogen trimers, metal excimers, metal-rare-gas excimers, metal-halogen excimers and rare-gas-oxygen excimers are also known.〔 Because of these excimer formations are unstable they disintegrate within a few nanoseconds converting their excitation energy to optical radiation. Because of the excimer molecule nature the difference between their stable excited state and weakly bound ground state amounts from 3.5 to 10 eV that is provided radiation of UV and VUV spectral range. The spectrum of excimer lamp radiation is characterized by an intense narrow emission band.〔 The full-width at half maximum of these bands depends on the kind of working molecule and excitation conditions and amounts from 2 to 15 nm. Hence, the excimer lamps are actually quasimonochromatic light sources. Moreover, about 70-80% of the whole radiation power of an excimer lamp is concentrated in this one emission band. Such sources are suitable for tasks of spectral-selective irradiation and can even replace lasers in some cases.〔〔〔 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Excimer lamp」の詳細全文を読む スポンサード リンク
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