A system for homogenizing a laser pulse emitted by a laser source in order to illuminate a target homogeneously, the system having, between the laser source and the target: a phase plate constituted by a plurality of subpupils capable of generating a plurality of delayed laser beams towards the target, the path difference Δd between two adjacent delayed laser beams being greater than or equal to the length of the temporal coherence Tc of the laser pulse, and focusing device; wherein the subpupils and the focusing device are adjusted so that the delayed laser beams are superimposed on the target in a homogeneous spot.