Ultra-fast micro machining of cylindrical parts with multiple ultra-short pulsed laser sources

Ultra-short pulsed lasers (pulse width 10ps) with high pulse repetition rates (1-8MHz) provide the possibility to process different kind of microstructures and sub-microstructures for generating surface functionalities. Several developments in the last years were focused on increasing the pulse repetition rate in combination with a higher scanning velocity to maximize the throughput. These methods are useful for a specific pulse rep.-rate / scan speed combination, but many technical barriers limit economic uses and further developments in this direction. For a further increase of the process velocity, a scaling of the laser sources / number of spots is necessary because in this way, the process control can be easily managed. Several aspects have to be considered in order to allow high precision laser micro structuring of surfaces. In this work, the theoretical background and the practical realization of a twin / quad ultra-short pulsed laser source as well as future developments are described