Development of a high precision self-adjusting laser mirror module

High machining availabilities are a key factor to ensure the productivity of laser material processing systems. The application of powerful CO2-laser sources in production systems with large ranges of travel require laser beam guidance systems with movable reflective optics. Rough environmental conditions necessitate regular servicing on the one hand and long travel an extremely precise adjustment of the reflector units after reassembly on the other hand. This manual and time-consuming adjustment of the reflectors leads to an extended production downtime. To address this issue, the Fraunhofer IPT has developed self-adjusting laser mirror modules with integrated sensors and actuating elements for automated laser beam guidance adjustment. This adjustment module features both a large angular adjustment range of +/-1.6 deg and a high resolution of 1.21 x 10-4 deg. The plane mirror can be tilted about two orthogonal and intersecting rotational axes and translated orthogonally to both of these axes. The integration of this reflector module into existing production systems requires a very compact design. The paper describes the mechanical setup and the development of an compact and high precise self-adjusting laser mirror module with high adjustment range and integrated holistic process parameter monitoring.