A device for cutting human or animal tissue including a femtosecond laser that can emit a L.A.S.E.R. beam in the form of impulses. The device directs and focuses the beam onto or into the tissue for the cutting thereof. The device further includes and element to shape the L.A.S.E.R. beam, positioned in the trajectory of the beam, and to modulate the energy distribution of the L.A.S.E.R. beam in the focal plane thereof, corresponding to the cutting plane.