Development of a UV laser source and Köster-prism-based DLIP for transparent material processing

This work presents a compact and power-efficient Direct Laser Interference Patterning (DLIP) optical configuration optimized for nanosecond-pulsed UV (266 nm) lasers. The system incorporates a galvanometer scanner for flexible beam delivery and a Köster prism on a motorized linear stage for beam splitting and for adjusting the texture spatial period. This new configuration allowed an improvement of the power efficiency from 69%, obtained in a conventional DLIP setup, to 87%. Simultaneously, the number of optical elements were reduced enabling a more compact optical configuration. This setup enables the fabrication of well-defined periodic line-like microstructures with variable spatial periods between 2 μm and 5 μm at maximum throughputs of 87 cm2/min on polycarbonate (PC) sheets. The results demonstrate the potential of this approach to establish a more compact, cost-effective, and scalable platform for functionalizing transparent materials.