Change in the radiation intensity distribution in a laser beam passing through a double-pass amplifier

A calculation was made of the distortion of the radiation intensity distribution in a double-pass laser amplifier with beams propagating at an angle to each other. The edges of the beam cross section were found to be more strongly amplified than its central part, so that the intensities at the amplifier output could differ by several tens of percent. On the other hand, on the intermediate mirror the radiation intensity at the edge was at least a few times higher than that at the center, which could result in damage to the optical components. The loading inhomogeneity of the optical components could be reduced by profiling the intensity of the input beam or by optimizing the specific input energy of the active medium in a transverse direction through the use of electron beams for pumping.