3D Printing of LuAG:Ce transparent ceramics for laser-driven lighting

The fabrication of transparent ceramics with freely designed geometries via 3D printing represents a paradigm shift in molding processes. The application of luminescent transparent ceramics (LTCs) in high-power laser-driven solid-state lighting has been significantly limited by traditional molding methods. Herein, dense cerium activated lutetium aluminum garnet (LuAG:Ce) transparent ceramics with good light transmittance (~40%) and complex structures were successfully fabricated using a digital light processing 3D printing method assisted by vacuum sintering. We developed an ink with a high solid content (~50 vol%) and good shear thinning property, and the optimal dye content (0.002 wt%) and exposure dose (80 mJ cm-2) to achieve 50 μm high-resolution printing were determined. A superhemispherical ceramic device with a convex curvature radius (R) of 11 mm, a concave curvature radius (r) of 10 mm, and a thickness of 1 mm was printed and sintered, which exhibited excellent laser-driven lighting properties and a high laser fluence threshold (19.22 W mm-2) owing to the special structure of surface guide grooves formed by 3D printing. Optical components prepared using 3D-printed LuAG:Ce LTCs with excellent physical and chemical properties have promising applications in next-generation high-power laser-driven solid-state lighting devices.