Characteristics of the radiation emitted by a pulsed CO2 laser with an unstable resonator and an exit mirror with the reflectivity varying over the beam cross section

The energy and the angular divergence of the radiation emitted by a pulsed CO₂ laser were determined at a constant pumping rate and for fixed parameters of the resonator using three different semitransparent exit mirrors and varying the thickness of the reflecting layer over the beam cross section. Radiation with a low angular divergence was generated in a wide range of pumping rates using an exit reflector with a smooth distribution of the reflectivity over the beam cross section.