Bearing cylinder type main supporting structure of large off-axis three-mirror space remote sensing camera

The invention discloses a bearing cylinder type main supporting structure of a large off-axis three-mirror space remote sensing camera. The invention relates to the technical field of space optical remote sensing, and solves the problems of low support rigidity and overlarge size envelope of a camera mirror assembly caused by large length-width ratio and large mass of main, third and folding mirrors of a camera due to the characteristics of long focal length and wide field of view of an optical system in the prior art, and the structure comprises a front frame, a rear frame, a main bearing cylinder, a truss rod assembly and a reinforcing rib assembly, the main bearing cylinder is connected with the front frame and the rear frame through screws. The truss rod assembly comprises two truss rods which are symmetrically arranged, the upper end of each truss rod is in positioning connection with the front frame, and the lower end of each truss rod is in positioning connection with the rear frame; the lower end of t