A study of the intensity distribution over the beam cross section in single-mode lasers

Study of the nature of the intensity distribution over the beam cross section at the outlet of helium-neon lasers operating on a single axial mode. The results of experiments on nonconfocal resonators are compared with theory. It is established that in resonators of semiconcentric type the intensity distribution differs from the theoretical, while in the case of other types of resonators the experimental data are in good agreement with the theory. It is shown that the deviation in the nature of the radiation intensity distribution in a semiconcentric resonator is related to the nonuniformity of the gain coefficient over the cross section of the active element.