A large field of view infrared staring imaging system based on liquid crystal grating
To solve the problem of difficulty for infrared optical systems to simultaneously meet the re-quirements of large field of view and high resolution. the mid wave infrared staring imaging system with split field of view imaging images multiple sub fields of view at different times in the same detector. How-ever,the system still has the drawbacks of inability to achieve seamless splicing and complex structure of liquid crystal shutter arrays. On this basis,this article proposed a new design of a large field of view mid wave infrared staring imaging system based on liquid crystal polarization gratings. By adding a rectangular stop at the first image plane and moving it backwards,the original 0.28° field of view loss was reduced to 0°. It achieved seamless splicing. The shutter array adopted a dual grating shutter structure,which elimi-nates the need for complex positional relationships. The liquid crystal shutter array was placed in a parallel light path to eliminate the longitudinal displacement between the main light rays caused by chromatic aber-ration and polarization. Using the proposed method,a mid-wave infrared staring imaging system was de-signed with an F-number of 3.25,a focal length of 130 mm,a wavelength range of 4.25 μm to 4.75 μm,and a full field of view diagonal of 10.8°. The MTF of each sub field of view unit is above 0.3@30 lp/mm. The final simulation results show that the system has the function of split field imaging and fine imaging quality.
optical designnarcissusliquid crystal gratingfield of view segmentation
万方数据
维普
