Intensity of radiation from a two-mode He–Ne laser with external signal injection

Theoretical and experimental investigations were made of the reaction of the laser power to an external radiation signal. The laser with an injected signal (LIS) was an He–Ne laser emitting radiation at the wavelength of 3.39 μm in the form of two orthogonally polarised modes. A study was made of the influence of the frequency detuning of the external signal from the LIS radiation, and also of the intensities of both radiations on the laser power response.