The contradiction between the field of view (FOV) and spatial resolution of imaging systems cannot be solved easily via the conventional single-aperture imaging, primarily because an optical system with a large FOV presents significant distortion, which severely affects the angular resolution at the edge of the FOV. In this study, a parallel compound-eye and secondary-imaging-system structure is adopted, and a multi-aperture lens array is used to image the spatial scene once. Sub-eye image planes are pieced together, integrated using an infrared fiber bundle, and then coupled with a detector through a relay system. Experimental results show that an optical detection system based on this technology can achieve the same imaging distortion (less than 2%) between splicing large and sub-eye FOVs as well as a uniform angular resolution under all FOV angles, thus effectively achieving high-resolution mid-infrared imaging with small distortion in a large FOV.