LED准直透镜设计

Desigin of LED collimating lens

针对目前LED准直透镜全反射部分多采用旋转抛物线或自由曲面从而增加加工难度的问题设计出一种结构简单、加工容易、准直效果好的LED准直透镜,该透镜由自由曲面折射面、全反射面和出光平面组成。采用自由曲面和全反射面相结合的方法,根据几何光学原理来构造自由曲面,利用Matlab编程计算出自由曲面面型数据并导入Solidworks建立透镜的实体模型。用Light Tools软件分析透镜的可行性。结果表明,在1500mm的探测面上可接收90.56%的能量,发光半角约为3°。为探讨LED尺寸对照明效果的影响,对透镜进行非序列光追迹。结果显示,当光源尺寸不大于1.4mm时,光能利用率达到50%时的照明距离超过7m。

The total reflection of most LED collimating lens adopts rotating parabolic or free-form surface, which increases processing difficulty, So a kind of LED collimating lens with simple structure, which is easy processing and has a good collimation effect is designed. The lens contains free-surface refraction surface,total reflection surface and exit surface. Combining the free-form surfaces with total reflection surface to construct free-form surface according to the principle of geometric optics. Using Matlab to calculate free surface data and import Solidworks, in order to estab- lish the model of the lens and using LightTools to analyze the feasibility of the lens. The results show that the detection surface in 1500mm can receive 90.56% of the energy, and the illumination half-angle is about 3°. In order to investi- gate the effect of LED size on lighting effect, non-sequential ray trace is analyzed by LightTools software. The results show that when the light source size is not more than 1. dmm, the utilization rate of light energy reaches 50% ,the illu- mination distance exceeds 7m.