ABSTRACT
This chapter begins with a semitutorial review of the basic physics of waveguiding and waveguide laser resonators. Perhaps the most surprising aspect of the use of radio-frequency (RF) discharges for gas lasers is not that it has proved so successful as an excitation technique, but rather that this success has been so long in coming. A waveguide laser is first, a laser, that is, an optical resonator containing an amplifying medium. RF-excited lasers are in some ways in their infancy and there seems to be some way to go in achieving a satisfactory understanding of the underlying physics. The important practical conclusion to be drawn from the results is that the voltage distribution along the waveguide should be nearly identical for “discharge on” and “discharge off” conditions. The two techniques described so far, aimed at solving the axial voltage variation problem, rely on shunt inductance to introduce a phase shift in the basic cosine variation, and smooth the voltage distribution.
