High strength laser cutting of high refractive index wafers for augmented reality

Abstract

As the industrialization of waveguide based Augmented Reality devices is progressing, considerations around design based shaping of the waveguides as well as robustness move into focus. Therefore, automated approaches concerning the cutting of eyepieces made of high index glass is a high priority. A promising approach for scalable free form cutting with high strength and precision is the utilization of ultrashort pulsed lasers. However, the plurality of possible laser process parameters and the different material compositions of high index glasses present a challenging field of optimization opportunities with respect to strength of the glass. SCHOTT AG and 3D-Micromac AG optimized a separation process towards high and predictable bending strength and integrated it into a modular machine concept freely scalable from lab to mass production use.