| Light emitting diode(LED) has advantages of long life, pollution-free and energy saving etc., so its application is in full swing, especially in the road lighting field. This paper summarizes the status of LED's application on road lighting including advantages as well as problems. For the light intensity distribution problem, this thesis develops two freeform surface lens, which were successfully used in the road lighting. This paper also proposes a solution to maintenance of road lights, which is called modularization of LED street lights. The main works go as follows:The first chapter analyzes LED's application in road lighting.The second chapter mainly introduces nonimaging optics and freeform surface method, particularly the Tailoring method in detail.The third chapter proposes a simple method for freeform lens design and presents two designs. The results of simulations and injection products are analyzed. Finally, the two lenses were integrated into LED road lamps and installed in different roads for testing. Results show that the design is reasonable.The fourth chapter proposes the modularization of LED street lamp system, which can benefit maintenance as well as other aspects. Further, several methods are also introduced to the modularization of LED road lights. In particular, a novel method called inner surface light modulation is used to design lens to meet light distribution for road lighting.The last chapter generalizes our work and gives a preview of the prospect. |
