Device for setting a focus position of a laser beam in a laser processing system, laser processing system with the same and method for setting a focus position of a laser beam in a laser processing system

摘要

The present disclosure relates to a device (200) for setting a focus position (z) of a laser beam (10) in a laser processing system (100). The device (200) comprises a computing unit which is set up to calculate a time-dependent value z of the focus position (z), the computing unit calculating the time-dependent value z of the focus position (z) based on a first parameter and a second parameter, the first Parameter specifies a size A of a laser power-dependent focus shift per power unit and the second parameter specifies a time constant τ of a change in the focus position due to a thermal lens by a factor of 1 / e, and a control unit which is set up to use a mechanism for adjusting the focus position (e.g. ) adjust the focus position (z) of the laser beam (10) based on the time-dependent value z of the focus position (z).