LED和梯度折射率透镜投影系统光路设计

Optical path design of LED and GRIN lens projection system

现有的数字光处理投影(DLP)系统采用色轮和中继透镜等元器件,由此导致投影系统结构复杂。针对现有技术的缺陷,本文设计了一种以三色LED作为照明光源,以梯度折射率透镜形成平行光的新型DLP投影系统。和传统的投影系统相比,减少了色轮、中继透镜、反射镜等元器件,简化了光学系统的结构。借助于Tracepro软件进行了模拟与仿真,对光线追迹的结果进行分析,分析得到整个投影系统的光斑均匀性为96.9%。结果表明本设计使投影系统的光路得到了简化,光斑的均匀性也得到了改善。本设计只需要选择合适的投影镜头,就可以消除LED面光源宽度过大对投影光斑的影响。

The existing Digital Light Projection（DLP）systems,in which the components such as color wheel and relay lens are used,resulting in a complex projection system.Aiming at this defection,a new DLP projection system was designed,where the three-color LED were used as the illumination light source and refractive index lens were used to produce the parallel light.Compared with the conventional projection system,components such as the color wheel,the relay lens,the mirror could be saved.Besides,the structure of the optical system was simplified.The simulation results and ray tracing by the Tracepro software show that the light spot uniformity reaches 96.9%.The results indicate that optical path of the projection system is simplified,and uniformity of the spot is also improved.The design only need to select the appropriate projection lens,that it can eliminate the influence of extended LED on the projection spot.