RF Excited Waveguide CO2 Laser with Low Thermal Drift

Abstract

Power stability is a fundamental requirement in most laser applications. Especially in relatively high powered lasers for material processing is the thermal stability of the cavity design of great importance. In the lower power region we find waveguide lasers intended for applications ranging from marking, scribing, cutting etc. to coherent radar and spectroscopy. The single frequency lasers, which are needed in coherent systems, are often dither stabilized and/or referenced to an external reference. The cavity design and its thermal characteristics have an important effect on the practical aspects of frequency stabilisation. Although a high degree of stability can be achieved without taking too much care of the thermal drift by using an elaborate feedback system1, 2, 3, 4, the demand on the feedback system can be substantially lowered by using a thermal compensated cavity design.