Life study of RF excited Hg arc lamps and CO2 waveguide lasers

An air cooled, electrodeless, high pressure Hg-arc lamp, excited with 800 W 2.45 GHz RF power, has delivered full output for the first 1000 hours. After 5000 hours, the 366 nm output power was 40 percent of the initial output. 140 MHz RF excited 2W CW CO2 waveguide lasers have shown life of 10,000 to 20,000 hours. This result was achieved with CO as well as with N2 bearing gas mixtures and for structures with internal electrodes as well as with capacitive wall coupling. One laser still had 60 percent of its original power left after 50,000 10-minute on-off cycles. Preliminary RF gas conductance measurements are also reported.