Single frequency operation of an argon ion laser using a three mirror cavity

An efficient coupled-cavity technique for achieving high power, single frequency laser operation has been described by Smith. An adaptation of this scheme is well suited to the argon ion laser, in which the large oscillating linewidth (∼10 gc) dictates an optical path length of about 1 cm in the mode selector part of the laser cavity. To simplify fabrication of the mode selector, the two high-reflectivity mirrors and the beam splitter have been combined into a quartz prism having dielectric coatings on its three faces.