High power disk laser technology – Design and potential for laser macro applications

Diode pumped solid state disk lasers will be soon available in power ranges that are convenient for the typical laser macro machining tasks as cutting and welding. The disk laser principle was used until now only for low power CW applications where the high beam quality was one main key advantage. Outlining the design of the up-to-date high power disk lasers the engineering solutions are explained which lead to reliable CW-Yb:YAG lasers for industrial applications. In comparison to existing laser technologies the advantages of the “disk laser technology” shall be briefly described. More than only the economic advantages as nearly negligible costs for the laser crystal as well as the very high efficiency the potential for laser macro machining applications is essential for the systematic evaluation of this beam source type. The high “beam quality” opens new perspectives for already introduced machining tasks as well as for new developed applications. For example the “remote welding” where the high beam quality enables the use of comparatively long focal lengths to realize working area dimensions which are convenient to machine complete structure elements without moving the work piece or the processing optic configuration. Applications as selective laser sintering can be done with higher precision by using a smaller focal spot to generate related thinner layers of material. Surface structuring tasks can also be done with a higher precision. Examples of up to date research activities for applications with high-power CW-Yb:YAG disk lasers at the TUHH are showing the potential for industrial applications.