Influence of optical inhomogeneities of the active medium on the spatial radiation spectrum in a CO2 amplifier

A theoretical investigation is made of the influence of thermal nonlinearity on the angular spectrum of interfering radiation in a CO₂ amplifier. It is found that small-scale intensity inhomogeneities can influence the phase characteristics of the radiation in the active medium of a CO₂ amplifier. An estimate is obtained of the divergence angle of the interfering radiation. An assessment is made of the extent to which the angular spectrum of the amplified radiation is affected by the time-dependent nature of the thermal nonlinearity mechanism and also by the motion of the active medium.