静、动态目标模拟离轴三反光学系统设计

Optical system design of off-axis three mirror for static and dynamic target simulation

基于单色像差理论,确定同轴三反光学系统的初始结构参数,通过二次曲面系数为0的偶次非球面的高次项之间的平衡,校正离轴系统引起的非对称性像差,同时结合DMD(数字微镜器件)目标生成器,设计出一款采用离轴三反光学系统的平行光管,为坦克承载的被测光电设备提供室内模拟目标。本光学系统的设计指标是工作波段为0.2~1.2μm,有效焦距为3000mm,全视场为2°,F数为8。结果表明,系统各视场的波像差均优于λ/34(主波长λ=0.6328μm),传递函数MTF均优于0.71@36.5lp/mm,接近衍射极限,成像质量好。对系统进行公差分析之后,系统的传递函数值远优于0.6@36.5lp/mm,合理的公差分配使系统加工难度降低,装调检测更加方便容易。

Based on the theory of monochromatic aberration,the initial structural parameters of the coaxial three-mirror optical system are determined.By balancing the higher-order terms of an even aspheric surface with a quadratic surface coefficient of 0,the asymmetric aberration caused by an off-axis system is corrected.Combined with DMD(Digital micromirror device)target generator,a collimator with off-axis three mirror optical system is designed to provide indoor simulation target for the tested photoelectric equipment.The design index of the optical system is working band is 0.2~1.2μm,the effective focal length is 3000 mm,all field of view is 2°,F number is 8.The results show that the wavefront aberration of all field of view of the optical system is better thanλ/34(the main wavelength is 0.6328μm),and the MTF value of the optical system is better than 0.71 at 36.5 lp/mm,which is close to the diffraction limit,and the imaging quality of the optical system is good.The tolerance analysis results of the optical system show that the MTF value of the optical system is much better than 0.6 at 36.5 lp/mm,and the reasonable tolerance distribution makes the system less difficult to process and easier to install and test.