Simple efficient C.W. TE, RF, CO2 laser with large cross-section

The design and operation of a water-cooled CW TE RF CO2 laser powered by a 100-W 1000-V 10-MHz source are reported. The device comprises a 7-mm-i.d. quartz tube containing 15:20:65 or 13:13:74 CO2:N2:He at 25-48 torr and located inside the RF circuits, a plane Si total-reflecting mirror, a 10-m-curvature-radius SeZn coupling mirror of reflectivity 80 or 93 percent, and drawn Cu tubing on each side to the quartz tube to carry cooling water supplied by a washing-machine pump. With mirror distance 32 cm and active length 26 cm, output of about 4 W is obtained, corresponding to nominal efficiency 4 percent and overall efficiency 2 percent, and the configuration is found to be easily maneuverable for such applications as surgical incisions. It is predicted that improvements to the RF coupling and RF power source can increase the emission from 170 to 300 mW/cm, permitting output of 25 W from a 100-cm sealed tube.