CCD航空相机动态分辨率检测系统设计

Dynamic resolution detection system design of CCD aerial camera

设计了一套CCD航空相机动态分辨率检测系统,系统入瞳直径D=200mm,焦距f′=2 000mm,视场角2ω=5°,利用光学设计软件Zemax进行仿真,设计结果表明,在奈奎斯特频率为40lp/mm的情况下,调制传递函数曲线值均高于0.5。采用波差法校正由长焦距所引入的二级光谱,同时,引入分辨率尺的概念,将每一块单独的分辨率板采用拼接的方式制作成300mm×24mm的分辨率尺,令分辨率尺在电机的带动下作匀速直线运动来模拟动态目标。该测试系统的设计能够在模拟飞机飞行的状态下,对其动态分辨率进行检测,检测精度1″,可广泛用于测绘、军事侦察和航空航天等领域。

A set of dynamic resolution detection system for CCD aerial camera was designed.The diameter of the entrance pupil is D=200 mm,the focal length is f′=2 000 mm,the angle of the field of view(FOV)is 2ω=5°.The system was simulated by Zemax optical design software,the design results show that,at the Nyquist frequency of 40 lp/mm,the modulation transfer function(MTF)curves are all above 0.5.The secondary spectra introduced by the long focal length were corrected through using the wave-deviation method.At the same time,the concept of resolution ruler was introduced,each separate resolution plate was made into a resolution ruler of 300 mm×24 mm by stitching,and the resolution ruler was driven by the motor to make a uniform linear motion to simulate the dynamic target.The design of the test system can detect the dynamic resolution of the aircraft under simulated flight conditions,the testing accuracy is 1″,and it can be widely used in mapping,military reconnaissance,aerospace and other fields.