The opposite beams in He-Ne ring lasers at 632.8 nm

In the paper the resonant interaction of the opposite beams in a He-Ne ring laser at 632.8 nm is discussed on the basis of experimental results. These results show that the stable laser generation is attained when no simultaneous interaction of the opposite beams exists in the laser system. In the experiment, the mode-locking generation was obtained by applying a combining mirror, reflecting some part of the output beam into the laser cavity