Shaping of the output beam in a pulsed gas laser with an unstable resonator

An examination is made of the transient process of output beam shaping in high-gain pulsed lasers with a short inversion lifetime. It is shown that to obtain an output beam with diffraction-limited divergence in such lasers, resonators with large magnifications M must be used. Results are reported of experiments on pulsed copper vapor lasers. Studies were made at different levels of excitation of the active medium over a wide range of variation of M.