Continuous operation of a long-lived CO2laser tube

A sealed-off CO
2
laser tube was operated with continuous, almost constant, power output at 10.6 μm for more than 1000 hours. A Ni cathode that was maintained at 300°C acted as a catalyst to regenerate CO
2
back into the tube from the oxygen and carbon monoxide formed in the discharge. By the time 1100 hours of operation had passed, 92 percent of the original CO
2
concentration was still available in the tube.