FREQUENCY STABILIZATION OF A GREEN HE-NE-LASER

A new process for stabilizing the frequency of commercially available 543-nm He-Ne lasers is described. The stabilization method is based on anomalous dispersion of the gain medium. A total of four green lasers have been stabilized-two at the National Institute of Standards and T echnology and two at the Institute of Scientific Instruments of the Cz ech Academy of Sciences-making it possible to study frequency variatio ns of the lasers relative to each other. We have also stabilized a 633 -nm laser by the use of the same method used for 543 nm.