A device and a method for controlling a laser system for the treatment of the eye lens by means of laser-induced disruptions. The laser system includes a femtosecond laser and a deflection unit for directing the laser beam and a detection device for detecting a value characteristic of the occurrence of disruptions being provided. The detection device is connected to the control device and the control device is adapted to determine a pulse energy for the laser system from the characteristic value and to actuate the laser accordingly.