Electric-discharge cw industrial CO2 laser

An experimental CO₂ laser is described, having an output power of 1.5 kW. The use of an electric-discharge unit containing a plane anode and nickel rod cathodes made it possible to couple 150 W into the active medium per cathode (input energy per unit mass 200 J/g, input power per unit volume 5.5 W/cm³, maximum electrooptic efficiency 24%). The service life of the cathodes exceeded 400 h. The relative stability of the output power, without recourse to stabilization, was 2–3% for continuous operation (without switching off) over a period of 8 h. The laser could be operated for 8 h without replenishing the active mixture and a helium-free CO₂–N₂–H₂O mixture could be used.