Reproducibility of the frequency of ring He-Ne/CH4 lasers stabilized using frequency-modulation resonances

Frequency-modulation resonances were used for the first time as reference points in stabilization of the emission frequency of ring lasers. These resonances appeared when the ring laser perimeter was modulated at a frequency greater than that corresponding to the homogeneous width of a line of an intracavity absorbing gas. The use of frequency-modulation resonances of the saturated dispersion made it possible to eliminate practically completely the influence of instability of pressure in the active medium on the reproducibility of the ring laser frequency.