Abstract
We report the separate TE01 and TE02 operation of a CO2 laser in a hybrid oscillator formed by placing a circular metallic waveguide and a focusing lens inside the cavity of an otherwise conventional laser. With the TE01 output focused into a passive waveguide outside the cavity, transmission in excess of 90% has been measured through a 31‐cm‐long, 0.5‐mm‐i.d. straight metallic tube. Bending increased the losses far more than originally anticipated.