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Dielectric barrier discharges (DBDs) are prized due to their excellent performance and their light emission in a UV band at low temperatures. Excimer lamps using DBDs filled with rare gas and under the atmospheric pressure are used in industry as VUV radiation sources or visible light sources in the presence of a phosphor. In this article, we report the experimental and theoretical investigations of Ne-50%/Xe-50% DBD, using a high voltage of 2 kV. The discharge was achieved and studied under the pressure of 250 mbar, at a frequency of 40 kHz. First, we have analyzed experimentally the electrical behavior of DBD Ne/Xe excilamp and have studied the temporal profile of total current density, discharge current density, applied voltage, plasma, and dielectric voltage. Then, we have compared the experimental electrical characteristics with a theoretical work. The computer model used is based on three modules: plasma chemistry, electrical circuit, and Boltzmann equation. The effect of applied voltage and gas pressure on the total current density measured is studied and discussed. Finally, we have simulated the Ne/Xe DBD with the same operating conditions of experience. The results of simulation illustrate the temporal variations of the discharge current density and applied voltage; the power deposited in the plasma by electrons and the species concentrations considered in the kinetic model. The total and partial lamp efficiencies are also investigated and discussed. [ABSTRACT FROM AUTHOR]

In this paper we use a two-dimensional fluid model and a `macroscopic' PDP cell to investigate the possibility of using large gap configurations with auxiliary electrodes to improve the efficiency of PDP discharge cells. The large gap allows operation in a transient positive column regime where energy is more efficiently deposited into xenon excitation, while the auxiliary electrodes are used to keep reasonable values of the operating voltage. Two types of auxiliary electrode configurations (floating and powered) are considered. The discharge characteristics and the discharge efficiency in exciting xenon are studied with simulations and by measuring the intensity of infrared emission from xenon and visible emission from neon in a macroscopic PDP cell. The results show that an efficient positive column regime can be achieved at reasonably low operating voltages when the auxiliary electrode configuration is carefully designed. [ABSTRACT FROM AUTHOR]

We report in this study detailed measurements of optical characteristics of the barrier discharge filled with Ne (50 %) and Xe (50 %) gas compositions. The discharge is driven by a sinusoidal voltage regime and was achieved and studied in the pressure of 250 mbar, at frequency of 40 kHz and for applied voltage going from 800 V up to 2 kV. The input electric power is measured with an oscilloscope, combined with a voltage probe and a current probe. The light intensity for the spectral region from 200 nm to 1100 nm was measured with a optical spectrometer. The lamp spectrum contained 826,877 nm, 822,021 nm, 879,995 nm, 881,999 nm, 902,998 nm and 915,011 nm radiations is studied in order to analysis the chemical kinetics in Ne/Xe mixture flat lamp in DBD emitting in the infrared (IR) and visible band. This study is done to explain the role of excited higher states in production of metastable states of xenon responsible for UV emission. The results discuss the effect of applied voltage and for different gas pressure on the luminance and efficacy of the lamp. The results predict that under the typical operating conditions of the DBD the total efficiency is very high with an optimum pressure at 400 mbar and an optimum voltage of 1200 V. [ABSTRACT FROM AUTHOR]