大视场凝视型红外共形光学系统设计

为提高导弹整流罩气动性能,增强导引头系统稳定性,增大观察视场,完成了共形整流罩结合红外鱼眼镜头的新型红外凝视成像导引头光学系统设计。光学系统采用的椭球形共形整流罩将反远距结构与f-θ成像相结合,通过控制像方视场角提高像面照度的均匀性。对不同结构共形系统的像差特性进行了分析。光学系统解决了大视场光阑像差问题,最终获得±90°的无渐晕观察视场,其冷光阑效率为100%,全视场MTF在15 lp/mm处均大于0.5,点斑均方根半径小于30μm,在半径为50μm圆内能量集中度为93%以上,像面相对照度高于85%,满足大视场光学系统的成像要求。

Design of infrared staring conformal optical system with wide field of view

In order to optimize the aerodynamic performance of missile domes,enhance the stability and enlarge the FOV,an infrared staring imaging seeker combining the conformal dome and infrared fisheye lens was designed.The solution used an ellipsoidal conformal dome,inverted telephoto lens and f-θ lens.Uniform illumination was realized through managing the imaging angle and pupil aberrations.Aberration characteristics of conformal dome were analyzed.The pupil aberrations at large FOV were solved.An optical system with ±90° unvignetted FOR,100% cold stop efficient was designed.The MTF is higher than 0.5 at the spatial frequency of 15 lp/mm across the entire field.The RMS radiuses of spot diagram are less than 30 μm;the geometric encircled energy is above 93% in 50 μm range;the relative illumination is above 85% at margin FOV.The specifications can meet the requirements of the wide field systems.