Collimating lens for light-emittin g-diode light source based on non-imaging optics
writer：Guangzhen Wang, Lili Wang, Fuli Li, and Gongjian Zhang
keywords：optical design,LED,non-imaging Optics
source：期刊
Issue time：2012年
Collimating lens for light-emitting-diode (LED) light source is an essential device widely used in lighting engineering. Lens surfaces are calculated by geometrical optics and Non-imaging optics (NIO). This design progress does not rely on any software optimization and any complex iterative process. This method can be used for any type of light source not only Lambertian. The theoretical model is based on point source. But the practical LED source has a certain size. So in the simulation, LED chip whose size is 1mm*1mm is used to verify the feasibility of the model. The mean results show that lenses have very compact structure and good collimating performance. Efficiency is defined as the ratio of the flux in the illuminated plane to the flux from LED source without considering the lens material transmission. Just investigating the loss in the designed lens surfaces, the two types of lenses have high efficiencies more than 90% and 99%, respectively. Most lighting area (possessing 80% flux) radiuses are no more than 5m when illuminated plane is 200 m away from the light source.