Optical design of rectangular illumination with freeform lenses for the application of LED road lighting

We present a freeform lens for application to light-emitting diodes （LED） road lighting. We propose a simple source-target luminous intensity mapping method based on Snell＇s law and geometric-optics analysis. We calculated different contours of cross-sections to construct a freeform lens with a smooth surface. The computer simulation results show that the lighting performance of a single freeform lens is not sufficient for road lighting. For the road lamp simulation, we adopted an oval arrangement of freeform lenses on a printed circuit board. In addition, we performed tolerance analysis to determine the tolerance limits of manufacturing and installation errors. A road lamp at a height of 12 m can create rectangular illumination with an area of 40 m ~ 12 m, 69.7% uniformity, and average illuminance of 24.6 lux. This lighting performance can fully comply with the urban road lighting design standard.

内渐进多焦点镜片的加工

介绍了加工内渐进多焦点镜片的自由曲面数控机床的基本结构及工作原理,开展了机床的加工工艺实验,用以改善内渐进多焦点镜片的光学性能。实验结果表明,车削阶段影响表面粗糙度的两个主要因素是镜片材料和切削速度;得到了抛光效果良好的两个抛光参数:抛光时间是50s—100s,抛光气压是0.03 MPa—0.06 MPa;不同材料的镜片车削后表面粗糙度不同,抛光后表面粗糙度基本相同。