POWER RADIO FREQUENCY CIRCUIT DESIGN FOR A SMALL CO2 SLAB WAVEGUIDE LASER

The design, construction, and test of a radio frequency oscillator-amplifier is presented in this paper. The RF circuit is inserted as part of the electrodes of an in-house-built compact CO₂ waveguide laser. Our circuit was designed to have a frequency at 81 MHz and its signal output between 90 W and 150 W. Capacitive discharge is evaluated over a period of time and, after a correct positioning of several inductors parallel-distributed along the laser electrodes, a steady and uniform plasma discharge was created. The overall RF circuit-laser test is done 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 conditions, a maximum optical output power greater than 10.7 W was obtained for an input feed RF power of 147 W.