Variable Double Stage RF Exciter for a CO2 Waveguide Laser
R. Lopez and R. Villagómez
The present work deals the design, construction and test of a radio frequency (RF) exciter for an in-house-built compact CO2 slab waveguide laser. The main characteristic of this power supply lies in the fact its design is based on MOSFET technology for both the oscillator and amplifier stages. RF output power is centred at 81MHzRF frequency signal between 100Wto 150W. The double stage system device has a minimum electric conversion efficiency of 64% and a harmonic distortion of 12.5%. The laser head and RF exciter have an electrical termination of 50 Ω , consequently we have a “match-impedance-circuit-free” system. The overall test for the entire system: RF excitation along with our CO2 laser head, are all made with a typical gas mixture of CO2-N2-He with proportion of 1:1:3 correspondingly and at a final pressure of 40 Torr. Under these specific conditions, a maximum optical output power of 10.7 W was obtained for the 147WRF feed.