Performance Comparison of Room-Temperature CO and CO2 Lasers, Used with the Same Apparatus.

Abstract

Output performance and beam characteristics have beencompared between room-temperature, rf-dischargeexcited CO and CO2 lasers, used with the same apparatus. When switching the operating laser type, cavity mirrors and gas mixtures were replaced. Under optimized conditions, output powers of 340W and 380W were obtained with the CO and the CO2 lasers, respectively. With the CO laser, a much higher slope efficiency (28%) was achieved (slope efficiency with the CO2 laser was 20%), suggesting that a much higher operating efficiency at higher inputs was obtainable for the CO laser. It was also confirmed, experimentally and theoreticall, that for the higher-ordered Gaussian mode beams, the divergence angles of the CO and CO2 lasers were comparable for the given laser cavities with the same diameter and length. For the fundamental Gaussian mode, however, a lower divergence angle, and hence, a more highly focusable beam, can be obtained with the CO laser than with the CO2 laser.