A method and machine for grooving, drilling or cutting of metallic workpieces

The invention relates to a method for piercing, drilling or cutting of metallic workpieces in a laser machining process, comprising: focusing a pulsed laser beam onto a machining location on the workpiece, detecting outgoing from the machining process radiation, determining a time of (t ie number of crossings of the gradient threshold value (dl The invention also relates to a machine for performing the method.