Improvement of laser irradiation uniformity in GEKKO XII glass laser system

Several key technologies for uniform laser irradiation are reported. This paper includes the uniformity performance as a result of the introduction of the random phase plate, the partially coherent light, and the beam smoothing by spectral dispersion into the New Gekko XII glass laser system. Finally we summarize the overall irradiation uniformity on the spherical target surface by considering the power imbalance effect. The technologies developed for the beam smoothing and the power balance control enable us to achieve the irradiation nonuniformities of around 1% level for a foot pulse and of a few percent for a main drive pulse, respectively.