A new type of postcompression system is provided by cascaded focusing and compressing, and a light pulse can be effectively compressed. The cascaded focusing and compressing postcompression system includes at least one cascaded focusing and compressing module. The cascaded focusing and compressing module includes a focusing unit and a compressing unit. The focusing unit is for nonlinear broadening a bandwidth of the light pulse. The compressing unit is for shortening a pulse duration of the light pulse. Therefore, the light pulse with broader bandwidth and shorter pulse duration can be provided. |