基于变焦结构的稀疏孔径系统MTF中频补偿  

Sparse aperture system MTF intermediate frequency compensation based on zoom structure

作　　者：刘婷 张蓉竹[1] LIU Ting;ZHANG Rongzhu(College of Electronic Information,Sichuan University,Chengdu 610064,China)

机构地区：[1]四川大学电子信息学院,四川成都610064

出　　处：《光学技术》2022年第6期647-652,共6页Optical Technique

基　　金：四川省重大科学仪器设备专项(2019ZDZX0038)。

摘　　要：稀疏孔径光学成像系统有固定的填充因子和确定的传函特性。为提高系统成像性能,增强其中频信息,分析了变焦结构对离散稀疏孔径系统成像的影响,推导了焦距、填充因子、调制传递函数(MTF)之间的关系式。设计了一个焦距为2857~4000mm范围内可变焦稀疏孔径成像系统。成像特性分析表明,系统焦距变小,填充因子随之增大,MTF截止频率减小,但MTF中频响应增强。通过图像融合将大填充因子清晰的中频条纹信息用于补偿小填充因子缺失的中频信息,仿真成像结果证明,不同填充因子下得到的图像通过融合后可有效提高整体图像各频段的成像质量。Sparse-aperture optical imaging system has affixed filling factor and certain transfer function characteristics.In order to improve the imaging performance of the system,and enhance its Intermediate Frequency(IF) information.the influence of the zoom structure on the imaging of the discrete sparse aperture system is analyzed,and the relationship between the focal length,filling factor and Modulation Transfer Function(MTF) is derived.A sparse-aperture telephoto imaging system with adjustable focal length in the range of 2857~4000 mm is designed.The analysis of imaging characteristics shows that when the focal length of the system decreases,the filling factor increases,and the cut-off frequency of the MTF decreases,but the IF response of the MTF increases.Through image fusion,the clear IF fringe information of large filling factor is used to compensate the missing IF fringe information of small filling factor.The simulation imaging results show that the images obtained based on different filling factors can effectively improve the image quality of each frequency band of the whole image after fusion.

关 键 词：变焦系统 稀疏孔径成像 填充因子 调制传递函数 图像融合 

分 类 号：O436.1[机械工程—光学工程]