High Efficiency, Fluorescent Excimer Lamps, an Alternative to CFLs and White Light LEDs

An innovative high efficiency xenon excimer lamp radiating at 172 nm has been built inside a section of a commercial compact fluorescent light (CFL) tube and has demonstrated the feasibility of a high efficiency mercury free white light source. Such lamps can be fabricated in various geometries and sizes and can operate with equal efficiency over wide temperature and power ranges. The excitation mechanism used is similar to that employed in mercury lamps, but without the power and geometry constraints of radiation trapping. This new system is highly compatible with phosphors as it operates at modest temperature in an inert gas and the 172 nm primary radiation is narrow band. A prototype fluorescent white light lamp achieved an efficacy of 90 lm/W. Higher values are projected. The lamp is rapidly switchable, is compat ible with dimmers, and is expected to have long operating life.