“十”字型四孔径视场部分重叠仿生热成像  

Bionic thermal imaging with cross-shaped four-aperture partially overlapped field of view

作　　者：杨建国 罗琳 金伟其[1] 李力[1] 何玉青[1] YANG Jianguo;LUO Lin;JIN Weiqi;LI Li;HE Yuqing(MoE Key Lab of Photoelectronic Imaging Technology and System,Beijing Institute of Technology,Beijing 100081,China)

机构地区：[1]北京理工大学光电成像技术与系统教育部重点实验室,北京100081

出　　处：《光学精密工程》2022年第9期1019-1028,共10页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.61871034);装备预研航天科工联合基金资助项目(No.6141B07090112);装备预研兵器工业联合基金资助项目(No.6141B012873)。

摘　　要：为了缓减探测器工艺受限条件下常规热成像系统视场和分辨率的矛盾,对多孔径布局模式、非重叠区域图像拼接算法以及重叠区域超分辨处理算法进行了研究。针对多孔径布局模式,提出了“十”字型四孔径和“十”字型五孔径视场部分重叠仿生热成像模式,并与“田”字型四孔径进行对比。采用ULIS公司微型非制冷红外焦平面探测器Micro80 GEN2,研制了“十”字型四孔径视场部分重叠仿生热成像实验系统,通过子孔径间的非重叠区域增大成像视场及基于重叠区域的亚像素微位移实现超分辨,构成类似人眼视觉的中心高分辨成像、边缘大视场搜索的视觉模式。对实验系统获取的分辨率靶标图像和外界场景图像进行了去盲元和非均匀性校正、基于透视变换的图像拼接以及基于焦平面探测器空间积分模型的超分辨处理,获得了空间变分辨率成像,并对图像进行了主客观评价。实验系统尺寸为180 mm×100 mm×100 mm,拼接总视场为单孔径相机的2.36倍,四孔径重叠区域占总视场的7.78%,成像分辨率得到了改善。该成像系统利用多个子孔径构成多目立体视觉,通过安装偏振片或滤光片还能实现偏振热成像或多光谱成像,具有广阔的应用前景。To alleviate the contradiction between the field of view and resolution in conventional thermal imaging systems with limited detector technology,the multi-aperture layout mode is studied with image stitching algorithm in the non-overlapped areas and super-resolution processing algorithm in the overlapped areas.The partially overlapped bionic thermal imaging modes of cross-shaped four-aperture and crossshaped five-aperture field of view are proposed for the multi-aperture layout mode to compare and analyze their uniqueness with respect to the Tian-shaped four-aperture.Using ULIS's miniature uncooled infrared focal plane detector Micro80 GEN2,a system of bionic thermal imaging is developed with cross-shaped four-aperture partially overlapped field of view.This provides a visual mode similar to human vision with high-resolution imaging in the center and large-field search in the periphery,using the non-overlapped areas to increase the imaging field of view and the sub-pixel micro-shift in the overlapped areas to achieve super-resolution.Image processing is performed on the resolution target image,wherein an external scene image is obtained by the experimental system,with blind element removal,non-uniformity correction,image stitching based on perspective transformation,and super-resolution using a spatial integration model for the focal plane detector.The spatially variable resolution images obtained are evaluated both qualitatively and quantitatively.The size of the experimental system is 180 mm×100 mm×100 mm;the stitching total field of view is 2.36 times that of a single-aperture camera;the overlapping area of the four apertures accounts for 7.78%of the total field of view,and the imaging resolution is improved.The imaging system uses multiple sub-apertures to form multi-view stereo vision to realize stereo imaging.Moreover,it can realize polarization thermal imaging or multi-spectral imaging by installing polarizers or filters,making it suitable for a variety of applications.

关 键 词：热成像 多孔径 仿生复眼 布局模式 超分辨 

分 类 号：TH703[机械工程—仪器科学与技术] TP391[机械工程—精密仪器及机械]