数字微镜器件在会聚成像光路中的像差分析

Analysis on Aberration of Digital Micromirror Device in Convergent Imaging Path

数字微镜器件(DMD)应用于会聚成像光路中时,其表面微镜绕各自旋转轴做偏转运动,且微镜相对平面反射镜呈非连续分布,这导致了经过DMD反射后的光束轴外视场主光线与轴上视场主光线存在光程差。利用几何光学和像差理论,在基于DMD的会聚成像光路中得到了DMD面上的像高、光线入射角度、DMD像素大小及偏转角与最终光程差之间的关系。分析了影响光学系统像质的因素及补偿方法,并通过仿真模拟和实验验证了理论的正确性。该研究结果对采用DMD器件的光学系统设计和装调均具有重要意义。

When the digital micromirror device(DMD)is applied in the convergent path of the imaging optical system,the deflection movement of the micromirrors on the DMD surface around their respective rotation axes and the non-continuous distribution with respect to the plane mirror directly result in an optical path difference(OPD)between the off-axis chief ray and the on-axis chief ray.Based on the geometrical optics and the aberration theory,the relationship between the final OPD and the image height on the DMD surface,the incident angle,the DMD pixel size and the DMD tilt angle is obtained in the DMD-based convergent imaging path.The factors influencing the image quality of optical system and the compensation method are analyzed.The correctness of the theory is verified by simulation and experiments.The research results have a great significance to the design and adjustment of optical systems with DMD devices.