Advancing LED efficiency through 3D-printed light extraction structures: from design to demonstration

This study presents an integrated modeling and experimental framework for optimizing light extraction efficiency (LEE) in light-emitting diode (LED) lens design. Leveraging recent advances in high-resolution LCD-based 3D printing, we directly fabricated three distinct lens geometries-dome, cone, and semi-spherical arrays-along with a planar reference. These microstructures, which were previously challenging and costly to realize using traditional fabrication techniques, are now made feasible, cost-effective, and tunable via 3D printing. Monte Carlo optical simulations, coupled with experimental measurements of external quantum efficiency (EQE), were employed to evaluate the optical performance. Strong agreement between simulation and experiment confirmed the reliability of our integrated approach. We achieved optimal LEE with a dome lens at a height-to-radius ratio of 1.0, a cone lens with a 20° semi-angle, and a 20 × 20 semi-spherical array. Notably, the 20° cone lens exhibited the highest overall LEE. This work highlights the transformative potential of 3D printing in enabling rapid prototyping and customization of microstructured LED lenses, offering a practical pathway toward high-efficiency, application-specific solid-state lighting components.