Operation of a high efficiency microwave light source

Spectroscopic studies have been carried out on a new, high efficiency, electrode-less, High Intensity Discharge (HID) light source. The lamp generates a microwave plasma in a cavity that is embedded in a quartz resonator, coupled to a 2.45 GHz magnetron by a short waveguide. The principal source of radiation is from excited rare earth atoms, produced in the discharge from the vapour above a mixture of metal halide salts, which leads to a rich and complex optical spectrum. Due to its high luminous flux, the lamp is particularly suited to industrial applications, where efficient lighting is required from high bay (6-10 m) ceilings.