Microwave excitation of metal halide plasma lamps

摘要: High pressure metal halide plasma (HID) lamps as compact light sources are characterized by high efficiency, excellent color rendering and long lifetime. Usually the lifetime is mainly influenced electrode erosion leading to wall blackening a reduction of luminous flux. Therefore it actual research interest have an electrodeless power input into HID lamps. More then ten years ago there was sulfur lamp with microwave excitation commercially available1. New trends lower units below 50 W including on could expand field application break new markets. This work discusses frequency behavior in lamps2,3. several geometries fillings were tested. The made quartz ceramics containing Ar ignition gas halides emitting substances. ignited external voltage pulse operated special resonator configuration at frequencies around 2.45 GHz. main energy inductive coupling varied between 5 30 W. supply built semiconductor basis. Input power, spectral distribution visible range vessel temperature observed vector network analyzer, fiber spectrometer infrared camera respectively. To enhance vapor additives, also vacuum chamber. Variations filling, lead changes output, temperature, circuit. Further experiments planed study influence other configurations shapes.