Design of Freeform Illumination Systems Based on Integrated Mapping Method and Feedback Optimization

In the field of non-imaging optics, the use of freeform lenses for achieving uniform illumination is of significant research importance. However, existing studies have primarily focused on uniform illumination design for planar targets and have made remarkable progress, while relatively less attention has been paid to uniform illumination on curved surfaces. To address this, this paper proposes a design method for freeform lenses aimed at uniform illumination on curved surfaces. The key to this method lies in utilizing the first kind of surface integral Equation to transform the problem from the Cartesian coordinate system on the target surface into a planar coordinate system, thereby significantly reducing computational complexity. Simulation results confirm the feasibility of the proposed lens design method in enabling the realization of high-efficiency, high-uniformity illuminance distribution on a curved surface via secondary optics for LEDs.