Tuning of the wavelength of a helium–neon laser from 3.3912 to 3.3922 μ
An investigation was made of the competition between the λ0 = 3.3912 μ and λ1 = 3.3922 μ lines emitted by a helium–neon laser. The theoretical output power at the wavelength λ1 was found to be 50% of the output at λ0. The experimental value was 40%. The rate of decay of the lower level of the λ1 line was determined and it was found that the rates of decay of the lower levels of both lines were independent of the pressure.