Common human fundus diseases, such as Age-Related Macular Degeneration (AMD), Diabetes Retinopathy (DR), Retinitis Pigmentosa (RP), etc., affect 60 million people worldwide. They are the main blindness cause of human. The autofluorescence of the fundus is closely related to the metabolism of the fundus. The autofluorescence imaging of the fundus can obtain more detailed and special fundus information, judge in advance the position where fundus diseases may occur, and accurately locate the position where fundus diseases have occurred. Due to the fact that eye fundus diseases often develop from surrounding areas, they are often missed in the early stages of the disease due to insufficient imaging field angles. Therefore, it is hoped that the imaging field angle can reach 90° at the pupil for a larger range of examination of the fundus. It is necessary to establish animal models for diagnosis and study human fundus diseases. As the structure and composition of rat eyes and human eyes are basically the same, rats are often used as animal models for human fundus disease research. Rat models can be used to replace human eyes for numerous studies related to human fundus diseases. At present, there is no method that can be directly used for ultrawide-angle fundus autofluorescence imaging in rats. Therefore, the development of methods and techniques for ultrawide-angle fundus autofluorescence imaging in rats is of positive significance for expanding the research methods of fundus diseases and developing related fundus disease inspection instruments. For this purpose, an ultrawide-angle fundus autofluorescence imaging system for rats was studied, which can perform fundus autofluorescence imaging on rats. Using rats to carry out related research on human fundus diseases can reveal the pathogenesis and process of human fundus diseases, and provide reference for the development of ultrawide-angle fundus equipment.The ultrawide-angle fundus autofluorescence imaging system for rats in this article is based on laser scanning confocal imaging technology. By using self-developed lens and two-dimensional scanning galvanometer, the scanning angle at the pupil reaches 90° (equivalent to a field of eye-angle of 132.3°), meeting the field of view requirements of ultrawide-angle fundus imaging. The fundus autofluorescence signal is obtained by using a filter with optimized light transmission range. Finally, the original images of rat fundus autofluorescence were registered and superimposed using SURF algorithm to obtain high-quality rat fundus autofluorescence images.Building an ultrawide-angle fundus autofluorescence imaging system in rats. The simulation shows that the illumination system not only has excellent image quality, its RMS radius is close to the Airy spot radius (Fig.3(b)), the MTF curve is close to the diffraction limit (Fig.3(c)), but also the aberration is small and the maximum distortion is only 8.7% (Fig.3(d)). The average horizontal field of view obtained from the three measurements was 90.38°, and the vertical field of view was 91.50° (Tab.2), which met the design requirements of the designed scanning field of view and could be called ultrawide-angle fundus imaging. At 488nm wavelength, the system resolution was 16.4 μm (Fig.8(b)), which was slightly larger than the theoretical resolution of 13.2 μm obtained from the RMS spot diagram radius. Considering the factors such as aberration, noise and measurement error, the test results of the system are in accordance with the actual situation. Sprague Dawley (SD) rats were used for imaging experiments to obtain fundus autofluorescence images of SD rats. The signal-to-noise ratio of three superimposed fundus autofluorescence images of SD rat was 8.64 (Fig.10(d)). The image quality can meet the requirements of ultrawide-angle fundus autofluorescence imaging. This system can be used for ultrawide-angle fundus autofluorescence imaging in rats.An ultrawide-angle fundus autofluorescence imaging system for rat was designed. The principle of the system is clear and the structure is simple. The self-developed lens is used to achieve ultrawide-angle fundus imaging with a pupil scanning angle of 90°, which is equivalent to 132.3° of the eye-angle. The system resolution is 16.4 μm at a wavelength of 488 nm. A confocal pinhole filter was used to filter out stray light in the focal plane, and the combination of fluorescence signal bands was set to obtain fundus autofluorescence signals. Finally, the three original ultrawide-angle fundus autofluorescence images of rats were superimposed, and the signal-to-noise ratio was increased to 8.64, which met the requirements of ultrawide-angle fundus autofluorescence images, promoted the research of fundus diseases, and provided a reference for the development of ultrawide-angle fundus imaging equipment.