Expanding direct laser interference patterning towards large areas, high throughputs, and 3D microstructuring: new configurations and strategies

Direct Laser Interference Patterning (DLIP) is an established technology for producing textured and functional surfaces using beam-shaped laser radiation. It consists of producing high-intensity interference patterns by overlapping two or more laser beams at the material surface. In this work, new possibilities for producing textured surfaces on metals and polymers using high-throughput concepts for DLIP are presented. The first concept describes the development of a new DLIP optical head (called xDLIP) with an outstanding depth of focus of approximately 10 mm, which can be equipped with fs, ps or ns pulsed laser systems. This approach makes this device ideal to treat large areas as well as three-dimensional parts. In particular, a setup using an industrial robot system is shown. The second approach includes the combination of a new DLIP optical system with a polygon scanner, showing the possibility to treat metallic and polymer surfaces. This includes configurations for reaching 7.0 and 21.0 μm spatial periods at throughputs beyond 1 m2/min. Finally, DLIP is implemented into a roll-to-roll process using a high-power picosecond pulsed laser source, in which the main laser beam is shaped into two elongated beams which go through a scanner system. Using this setup, aluminum and copper foils with thicknesses of 20 μm and 9 μm, respectively, are processed.