Effect of stimulated scattering in the active medium on the output divergence of an electric-field-pumped gas laser

The effect of stimulated scattering (SS) on the divergence of light in CO2 lasers with electric-field pumping is investigated. The study is restricted to light pulses no shorter than 10 microsec and angles of not less than about 0.0005 rad. Results indicate that SS in the active medium of a laser is an important physical factor which hinders the attainment of the diffraction limit. It is noted that the use an external resonator could significantly reduce the nonlinear effects.