Lighting from thin (<1 mm) sheets of microcavity plasma arrays fabricated in Al/Al₂O₃/glass structures: Planar, mercury-free lamps with radiating areas beyond 200 cm²

Flat lamps, having radiating areas as large as 15 × 15 cm² and comprising arrays of Al/Al₂O₃ microcavity plasma devices, have been fabricated and characterized in the rare gases. Sealed arrays of devices with microcavities having diamond-shaped cross-sections yield lamps with an overall thickness of ∼800 νm (of which ∼500 νm is the quartz output window) and luminance and luminous efficacy values greater than 1600 cd m^-2 and 10 lm W^-1, respectively, are observed in preliminary experiments in which microplasmas in a Ne/20%Xe mixture illuminate a commercial green phosphor in a transmission arrangement with the ∼10 νm thick phosphor film situated immediately above the array. Efficacy values well in excess of 20 lm W^-1 are expected when the array design and microcavity-phosphor geometry are optimized. Fully flexible arrays sealed in polymeric packaging have also been demonstrated, thereby providing access to new opportunities for lighting in which lightweight arrays are mounted onto curved surfaces.