Intracavity dye laser spectroscopy as a gain probing technique

A He-Ne discharge tube with gain at 6328 A, a flashed ruby rod with gain at 6943 A, and a brightly fluorescing flame were each inserted into the cavity of a flashlamp-pumped dye laser. The influence of the two gain media on the dye laser differs significantly, apparently due to their dissimilar saturation characteristics. Refractive index effects were also observed. The flame experiment demonstrates the efficacy of the intracavity technique as a simple relative population probe.