Reduction of laser imprinting using polarization smoothing on a solid-state fusion laser

We demonstrate a laser beam-smoothing technique known as polarization smoothing. A birefringent optical wedge splits the individual laser beams into two orthogonally polarized beams that, when coupled with a distributed phase plate, produce two speckle patterns shifted with respect to one another. This instantaneously reduces the on-target nonuniformity by a factor of √. We measured this reduction optically and its effect is demonstrated in laser-driven targets.