We report spatial and temporal dispersion compensation for fan-out of femtosecond pulses with a low-frequency diffraction grating by means of a hybrid diffractive–refractive lens triplet. In this way, we achieve a multifocal light structure with nearly diffraction-limited light spots even for pulse duration. The spatial chromatic compensation, which drastically reduces the lateral walk-off of the various spectral components, also allows us to improve the available bandwidth at the dispersion-compensated diffraction orders. In fact, the temporal width of the output pulse is essentially limited by the group-delay dispersion term, which is shown to be small. The high spatiotemporal resolution provided by our proposal permits parallel multifocal processing of materials with femtosecond pulses.
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