Characteristics of unstable resonators with field distortions in their components. I. Cylindrical mirrors

Numerical solution of the integral equations for an unstable confocal resonator with cylindrical mirrors, obtained by the fast Fourier transform method, is used to study the influence of field distortions in the components of the resonator on its characteristics. Distortions of the field typical of a resonator filled with a fast-flowing active medium are considered: they include asymmetric distortion of the mirror surfaces simulating thermal deformation and small-scale random phase inhomogeneities of the active medium. Calculations are carried out for lasing in a supersonic stream of mixtures of carbon dioxide, nitrogen, and water vapor in the case of various values of the gain.