CO2 Waveguide Laser Resonators

Over the past 20 years or so the waveguiding principle and waveguide resonators have been applied to a number of laser types, including dye lasers, diode lasers, helium–neon, helium–xenon and carbon monoxide lasers, excimer lasers and far infrared lasers. This chapter reviews some of the important practical developments in waveguide CO 2 lasers, emphasizing those issues which relate to the resonator design. It outlines practical characteristics of waveguiding in the 10µm spectral region. The chapter also includes a discussion of the main options for resonator design, giving practical examples where appropriate. It discusses the optical design implications of waveguide lasers which incorporate multiple discrete gain lengths, with the beam optically folded from guide to guide. The chapter concludes with a brief review of some recent work on resonators for slab–shaped gain media, which combine features of both waveguiding and unstable resonators.