Maximizing the output power of a CO2 laser using theTaguchi technique

The results of an experiment aimed at optimizing the output beam power of an industrial fast-axial-flow CO₂ laser machine using the Taguchi method are reported. Four control factors (design variables) were explored: blower speed, laser gas pressure, cooling fans, and output mirror transmittance. The various parameters were assigned to a modified L18 orthogonal array. The experiment was conducted with two repetitions and complete randomization within block was practiced. It was found that higher laser power could be obtained with a blower speed of 2526 r.p.m., laser gas pressure of 62 torr, cooling fans, and output mirror transmittance of 40%. The laser gas composition was kept constant at 5% CO₂, 14% N₂, and 81% He. Twenty confirmatory tests were performed and the results fell within the predicted 95% confidence interval