The Helium-Neon laser

Abstract
The physical principles underlying the design and operation of the Helium-Neon laser are discussed. The various ways in which the system may be used to produce laser radiation are reviewed, as are properties of the radiation, such as its frequency structure, monochromaticity and power density. Attention is also given to the effects of external magnetic fields on the system and methods of stabilization of the output frequency. Finally, the various applications of the device are discussed.