Research About Space-based IR-optical System For Space Object Detection

The space-based infrared optical system has great value in the use of space objectsdetection. Its advantage is very obvious especially for the detection of objects in theshadow of the Earth. This thesis is about the detection of the satellite in the low orbitaround the Earth. A space-based infrared optical system is designed. It worked in thelong wave-band which is the main radiation of the space object. The detection distanceof the system reaches to1000km.The main work of the thesis includes several aspects as follow. First, the infraredradiation of the object orbited around the Earth is studied, including the radiation fromitself and outside. The radiation is computed and its graph is given. Second, the formulaused to compute the aperture of the infrared optical detection system is deduced basedon the noise equivalent temperature difference of the infrared detector. Choosing a kindof cooled infrared detectors, the design parameters of the infrared optical systemsatisfied the detection range can be computed. Third, the space-based infrared opticalsystem is designed. Its structure is a R-C system with a group of lens used for turningthe image. This structure can make the cold stop matches with the entrance stop. Theoptical system realizes a100%of cold stop efficiency as well. In the temperature of80K～100K, the athermalization design of the system is achieved and every assessmentindex of optical detection system is satisfied. Fourth, the lens loop of the system isdesigned and the analysis of the stray radiation is made. The result shows that the strayradiation from the off-axis and the system itself are both controlled effectively...