Design & Research On Street Illumination Optical System For LED Based On Free-form

Under the background of high rapidly development of the global economy, global energy shortages intensified increasingly. Face the urgent crisis, Chinese government strongly advocated taking the road of sustainable development. While the exploitation of new energy and renewable energy, but also strong proponent of a low-carbon lifestyle. According to the National Bureau of Statistics indicated that the total power generation in 2013 was 5.39755 trillion KWh, which accounted for 13% is used for illumination, and almost equal to nine times annual generation capacity of the Three Gorges Dan. Therefor, energy saving on illumination was becoming one of the effective measures at national energy saving. The most promising source is Light Emitting Diodes(shot for LED) in the new sources. With the booming development of LED technology, comparing with the traditional sources, LED has stupendous advantages such as energy saving, environmental, long life, high speed etc.. So, more and more extensive applied in whole lighting fields, such as landscape lights, traffic lights, car lights, special lighting, general lighting fields. Given these, it is considered as the most valuable lighting source in new century.In the above application, the precondition required reallocate the light emitted from LED, also means second optical design. This article researched based on the background of street lighting, the research work focusing on the optical part of the street lighting design. Firstly, presents a brief introduction of LED’s basic theory and the relevant development status for the street lighting, accordingly, draw forth the free-form optical design. Secondly, on the basis of the principle of optical and differential geometry, lens light distribution program are designed for street lighting when the lamps projection in the middle or the medial of the road, otherwise, the appropriate light distribution program in roadway annular island also been designed. Throughout the design process, establish a mathematical model of the lens surface respectively, Matlab software was used to program the free-form surface and solve it, then, Solidworks software was used to establish the solid model. Tracepro software was used to ray tracing the light and simulate the optical system. From the simulating results, the circumstances on the road surface can be simulated and analyzed in DIALux. The results got from DIALux indicate that the uniformity, glare, peripheral illumination factor and other optical factor of the optical systems achieve the requirements of "CJJ45-2006 city road lighting design standards". Therefore, the feasibility of these design are verified. Finally, according to the research of this article have a summary, and have a prospect of the entire lighting design on the basis of the research of this article, so that better guide the working direction for the future.