Narrow-band CO2-TEA laser for efficient FIR laser pumping

To reduce the linewidth mismatch between the emission lines of a CO
2
-TEA laser and the absorption lines of a low-pressure FIR gain medium a tiltable Ge etalon has been introduced into the TEA resonator. The resulting spectral compression and tunability increase the energy conversion efficiency in a TEA laser pumped CH
3
OH laser by as much as a factor of 37 and has led to the observation of 14 new FIR laser lines.