基于延迟积分机制的长波红外热像仪图像锯齿消除方法研究  

Image Aliasing Elimination Method of Long-Wave Infrared Thermal Imager Based on TDI Mechanism

作　　者：李哲[1] 孙伟[1] 丁捷[1] 詹东军 王鹏[1] 朱海刚 LI Zhe;SUNWei;DING Jie;ZHAN Dong-jun;WANG Peng;ZHU Hai-gang(Huazhong Institute of Electro-Optics—Wuhan National Laboratory for Optoelectronics,Wuhan 430223,China)

机构地区：[1]华中光电技术研究所—武汉光电国家研究中心,湖北武汉430223

出　　处：《光学与光电技术》2022年第6期63-69,共7页Optics & Optoelectronic Technology

摘　　要：基于延迟积分(Time Delay Integration,TDI)机制的长波红外热像仪在军事、航空、航天领域应用广泛,通过光学扫描,能够同时实现大的成像视场和较高的空间分辨率。基于TDI机制的长波红外热像仪的探测器采用TDI工作模式。由于TDI与光学扫描之间匹配精度的问题,在对景物成像时,景物的边缘常常存在参差不齐的锯齿状现象,影响目标提取和识别,降低了图像的观感。分析了因扫描视场和光学视场不匹配导致景物图像产生锯齿的现象,提出了一种将探测器上像元分布的空间物理间隔转换为时间延迟的锯齿消除方法。时间换空间的方法能有效消除景物图像锯齿,真实还原小目标边缘的细节,大大提升了图像的观感,该方法已广泛应用于红外搜索跟踪(IRST)系统、红外光电系统等装备。Long wave infrared thermal imager based on TDI(Time Delay Integration)mechanism is widely used in military,aviation and aerospace fields.Through optical scanning,large imaging field of view and high spatial resolution can be achieved simultaneously.The detector of the long wave infrared thermal imager based on TDI mechanism adopts TDI working mode.Due to the problem of matching accuracy between TDI and optical scanning,when imaging a scene,the edge of the scene often has uneven sawtooth,which affects target extraction and recognition and reduces the image appearance.In this paper,the phenomenon of aliasing in the scene image caused by the mismatch between the scanning field of view and the optical field of view is analyzed,and a method to eliminate sawtooth by converting the spatial physical interval of the pixel distribution on the detector into a time delay is proposed.The method of time to space can effectively eliminate the sawtooth of the scene image,restore the details of the small target edge,greatly improve the image appearance,and the method has been widely used in IRST systems,infrared photoelectric systems and other equipment.

关 键 词：延迟积分 扫描 匹配 锯齿 中心距 焦距 

分 类 号：TN219[电子电信—物理电子学] TP391.41[自动化与计算机技术—计算机应用技术]