The Characteristics of a Positive Column in a Rectangular Discharge Tube

Abstract

The rectangular discharge tube will be used for the back light source of a liquid crystal display for a personal computer or color TV because the uniform luminance over a wide range is expected. The optical characteristics of the positive column of the rectangular discharge tube depend on plasma parameters in there such as an electron temperature and an axial electric field. Therefore, it is important to investigate the relation between the optical characteristics and the plasma parameters in the rectangular discharge tubes. In this paper, the radial distribution of the radiation intensity and the spectral characteristics were measured as functions of gas pressure and discharge currents for a rectangular discharge tube. Then the plasma parameters were obtained. The gases used were neon and neon — oxygen mixtures. The tube used for measurement was rectangular profile of 2×4 [cm]. The current over the range 10 — 50 mA was examined. The gas pressure was varied from 0.1 to 7 Torr. Then the experimental results were discussed qualitatively.