Binsong and Fraunhofer Institute set up a new laboratory for ultra short pulse l

Binsong and Fraunhofer Institute of Laser Technology (ILT), photoelectric giants, announced the establishment of an application laboratory dedicated to the advanced laser material processing of ultrashort pulse lasers. In Aachen, Germany, the two partners jointly developed a spatial light modulator head (SLM) for industrial processing, which can be used for a wide range of applications by combining customized dynamic beam shaping with large laser average output power. The average output power of Hamamatsu's SLM can reach 150 watts.

In the joint application laboratory of Binsong and Fraunhofer ILT, a scanner based process head with integrated high-power SLM can be used to study the manufacturing process.

Photo source: Fraunhofer ILT, Aachen, Germany

Multi beam system is the key

Ultra short pulse (USP) laser can process almost any material with the highest accuracy. In order to improve the economic benefits of USP processing, different hardware methods are used to solve the problem of increasing the high average laser power of more than 100 watts, so as to improve the processing speed and reduce the unit cost. A common way to achieve high laser power is to divide high energy radiation into many separate beams. This method has been applied in industry, especially in 2D laser material processing or in generating periodic patterns, such as filters.

The phase mask is used to generate a parallel beam pattern with a large number of partial beams from an incident beam, which works dynamically with a spatial light modulator (SLM) or statically with a diffractive optical element (DOE) made of glass. SLM can dynamically change the phase mode, so it can also change the beam matrix, while the static DOE can withstand higher average power. Because the beam characteristics can be easily adjusted and customized, SLM is particularly suitable for developing manufacturing processes using USP laser radiation. This applies to both the beam profile and the arrangement of individual beams in the pattern.

In batch production, SLM has advantages if the beam pattern must be dynamically changed during processing. If the beam parameters are known and static, DOEs becomes a better choice because of its insensitivity.

Joint application laboratory

The two partners established a joint application laboratory in ILT, Fraunhofer. In this laboratory, ILT is helping its customers develop manufacturing processes. In addition, it uses its developed knowledge and technology in new research projects. In this laboratory, an industrial prototype is ready for the development of manufacturing processes. This includes a scanner based process head, which integrates Hamamatsu's new high-power SLM. The head is integrated into a 3-axis machine with a 150W USP laser. This SLM has been optimized for high average power and is currently being introduced to the market. Hamamatsu received the support from the Japanese government and established a new laboratory according to the Inter ministerial Strategic Innovation Promotion Program (SIP).

In Aachen, since May 2022, the system with the new SLM has been used in various processes and applications. The joint team has studied surface and volume ablation for different beam profiles and focusing diameters. The flexible liquid modulator eliminates the need for tool replacement. When using high average laser power, the heat distribution in the workpiece becomes more and more important, and the speed and efficiency of USP process are also improving. With the support of Aachen University of Technology, ILT has been able to fully simulate these processes. In this way, the energy distribution can be optimized to optimize the heat input in the parallel beam distribution.

Source: OFweek