Spatiotemporal dynamics of femtosecond laser pulses during apodization by a serrated diaphragm

We report a numerical investigation of the spatiotemporal dynamics of a femtosecond laser pulse after aperture separation on a circular serrated diaphragm and a spatial filter. It is found that the use of serrated diaphragms together with a spatial filter can markedly reduce the negative impact of diffraction effects on the spatiotemporal dynamics of the pulse. Criteria are formulated to determine the parameters of the separation scheme in order to avoid significant distortions of the radiation properties during subsequent focusing.