High-power CO2 laser beam intensity distribution is nonuniform, which is caused by inhomogeneously gain medium. Aiming at that nonuniform distribution, a new resonator consisting of a roof mirror is designed. At the same time the beam intensity distribution is modified to obtain greater temporal uniformity by reflector's periodically vibrating. Output modes of both the resonator with a pair of parallel-plane mirrors and the former new resonator are obtained by numerical simulation calculation with Fox-Li iteration. Simulated results are presented that with the resonator uniformization ofthe beam intensity distribution can be achieved.
This paper describes a new approach for flattening high-power and high-gain CO2 lasers. A periodic change of curvature of concave mirror causes beam modes to jump in the course of time. Averaging out these beams results in an intensity profile with good uniformity. It is also compared to the output intensity ofthe resonator without vibration.