Non-imaging Optical Design Of LED-based Lighting System

At present, LED lighting has been expanded in various lighting. Without secondary light distribution, lighting effects of LED cannot meet the requirements in certain lighting situations. In order to improve the efficiency of the illumination system with specific requirements, it is necessary to study non-imaging optics.Firstly, the development of non-imaging optical design in recent years is discussed; then the methods of designing free-form surface based on non-imaging geometry theories and mathematical knowledge are conferred. On the basis of the above, a theoretical method to design free-surface is obtained. Two lenses designed by this method herein are the most typical models in non-imaging LED lighting system, one of which can obtain a homogeneous rectangular light spot, and the other can obtain a uniform circular light spot. In the process of constructing the free form surface, the most important problem to be solved is finding the relations among light, free-form surfaces and target illumination. A method to construct the freeform surface has been raised to do the theoretical calculation. In this method, the discrete-points of free-form surface are calculated by numerical solution method, and then the lens3D model can be formed; finally, the simulation of lighting systems proved the feasibility and correctness of the method to form the free-form surfaces.