<title>High-performance fast-axial-flow radio-frequency discharge-excited CO laser</title>

Abstract

The parametric study has been performed to improve the output performance and the beam properties of a fast axial flow, radio frequency (rf) discharge excited CO laser, where an emphasis is placed on the optimization of an electrode configuration. The laser has a single discharge section which consists of a quartz tube and a pair of cylindrical outer metallic electrodes. The measurements have shown that the discharge uniformity is considerably influenced by the curvature radius of the outer metallic electrodes and the air gap spacing between the tube outer wall and the metallic electrode inner surface at the downstream edge of the electrodes. In the experiments, the most uniform discharge over the tube cross-section has been obtained for a metallic electrode curvature radius of 16 mm and an air gap spacing 0.5 mm. As a result, a maximum specific output obtained has reached 1200 W/m at an entrance gas temperature of 140 K, a corresponding rf to optical conversion efficiency being 21.2%. Furthermore, we have also succeeded in efficient room temperature operation with Xe-free mixtures.© (1994) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.