LCoS微型投影光引擎杂散光分析与抑制

Stray light analysis and suppression of LCoS micro-projector optical engine

为抑制LCoS光引擎的杂散光,在TracePro软件中建立了光引擎的光机模型,运用蒙特卡罗方法对该系统的杂散光进行了分析。通过仿真模拟及实验发现PBS棱边、成像透镜边缘、镜片隔圈以及镜筒内表面为产生杂散光的关键面。为此使用挡光片、表面发黑、镜片边缘及隔圈涂黑等方法对杂散光进行抑制。仿真及实验均表明上述方法可有效抑制杂散光。

The opto-mechanical model of LCoS optical engine has been established in TracePro software for the purpose of suppressing stray light.Stray light is analyzed using Monte Carlo method.The edges of PBS prism and imaging lenses,the inner surfaces of cone and spacer are found to be the key surfaces which will generate stray light by simulation and experiments.In order to suppress the stray light,not only baffles are used,but also key surfaces are blackened.Absorption paint is smeared on the edges of the imaging lenses and inner surfaces of the spacer.Simulation and experiments both prove that above methods can suppress the stray light effectively.