We have recently applied the principle of the hollow dielectric waveguide laser to the CO
2:N
2:He system. The resulting lasers are very compact and give output powers of a few watts. The narrow bore capillary (1 mm dia.) used as the waveguide, allows CW operation at gas pressures up to

atmosphere. The increase in pressure broadened linewidth has resulted in 3 nanosecond pulses in a forced mode locked laser. Single frequency lasers with a large tuning range should also be possible. Many applications are possible in the fields of molecular spectroscopy, air pollution studies, and as a local oscillator in an optical receiver.