High Power CO-Overtone Laser

Abstract

A modified electron beam controlled pulsed CO_2 laser is used as a multi spectral multi purpose test bed in order to generate high power fundamental and first overtone laser transitions in CO. The revisited concept includes an all solid state power supply which provides a highly reproducible operation at pulse repetition frequencies of up to 100 Hz. The active gas mixture is recirculated in a closed loop and kept at near room temperature using conventional water cooling. Discrimination of the CO fundamental band is obtained by using specially coated dielectric mirrors and introducing additional intracavity diaphragms. Unprecedented laser pulse energies of 25 J are reported in the overtone transitions covering a spectral range between 2 µm and 3.5 µm. Further scaling of pulse energies is expected in the near future using larger diameter resonator mirrors.