Fabrication of Freeform Lens Based on Ionic Wind for Chip-on-Board Light-Emitting Diodes

In this study, a novel method for the fabricating silicone lenses is proposed based on ionic wind. In such a method, the normal stress on the air-liquid interface is induced and adjusted by ionic wind, which is applied around liquid lens material. Through adding a specific shape of mask, the lens can be tailored into desired freeform morphology. Experiments are conducted and freeform lens of dual stripe and meniscus shapes are fabricated by configuration of specific mask. Besides, the influence of thickness of silicone gel and the shape of micro-patterns upon optical performance is analyzed by optical simulation, the Monte Carlo ray-tracing method. Results show that the improvement of LEE with the dual stripe lens reached 41.02%.