ABSTRACT
Excimer lasers, which are finding uses in applications ranging from materials processing to inertial confinement fusion, represent an increasingly important area of laser technology. Rare gas halides (RGH) lasers are characterised by high gain, relatively large gain bandwidth and significant non–saturable losses. RGH lasers which are excited by electric discharges (by far the most commonly–used technique) have excitation durations which are limited by discharge stability to times corresponding to only a few round trips of the laser cavity. Many such systems, which combine the short pulse capability of dye lasers with the high power capability and useful UV wavelengths of the excimers, are in existence in laboratories throughout the world. Excimer lasers operate with hostile gain media containing highly reactive gases undergoing discharge excitation. The UV output itself is also a source of problems for transmissive or reflective optics. For many applications excimer lasers with simple stable resonators provide useful high power output in the near UV.
