LED Freeform Lens Design for Street Uniform Illumination
He Zhihua
Dong Qianmin
Wang Shaolei
Li Min
Abstract：Given the complexity and particularity of the LED in the application of street lighting , this paper presents a new lens design method for street uniform lighting based on non-imaging optics .Using the theory of differential geometry to set up the first-order quasi-linear hyperbolic partial differential equations of the freeform lens surface , and solve it by numerical solution in matlab , using the data of the lens profile , the lens model is established in SolidWorks .The designed lens can convert the Lambert distribution of the LED into the bat wing distribution for street lighting .The designed optical system simulated with ray-tracing in TracePro, the results show that the overall uniformity of the 10m distance target plane is above 85%, and the efficiency is 89 .2%.This optical system still maintains good lighting effect when point at extended light source .Not only is the effective illumination area in line with expectations , but also can keep the uniformity above 80%.The street lighting system , which uses the designed lens consisting of 5 ×10-in modular, simulated the lighting effects in DIALux .The results show that the uniformity achieves 83% on road surface , which conform the national standard .
Keywords：partial differential equationsLED optical designuniformitystreet lighting
Publication Date：2014-01-01
Online Publishing Date：2025-08-15(First online date of this platform, not the publication date of the document)
Pages：5( 85-89 )