Transition selection with adjustable outcoupling for a laser device applied to CO2

In this paper we discuss the possibilities and realization in high-power systems of a narrow-band reflector with adjustable high reflectivity and with continuous tuning over a large frequency region. We describe a design for both low- and high-gain systems. For the experimental realization of a low-gain system we used a CO2laser and studied a continuous range of 65 transitions of the001-020and 13 transitions of the 0111-1110 vibrational band. With a cavity containing a dc discharge 130 cm long, for each band we found a continuous range of single oscillating transitions with output powers up to 15 W. Finally, we propose an experimental solution for continuous tuning of a high-gain system as, for instance, the central part of the001-100vibrational band of CO2.