Wafer-level integration technology for multi emitter high power fiber coupled lasers

The main package technologies for fiber coupled lasers are single emitter packages such as modified TO-packages or High Heat Load packages. In both cases, the packaging costs are significantly higher than the costs of the single laser diode. Furthermore, the scalability of the optical output power is only possible by varying the input current. Due to the characteristic curve of a laser diode this goes along with a poor wall-plug-efficiency. To achieve a significant improvement in both cases, new packaging technologies are required. In this paper a new packaging approach is presented, which can be used to couple the power of one or more laser diodes into one fiber without using additional beam shaping elements. The combination of the single optical paths is realized by a planar lightwave circuit in a glass substrate. To ensure cost-efficiency only standard processes of electronic manufacturing are used. Furthermore, wafer-level fabrication contributes to the possibility of mass production.