Analysis on different rates image motion of space camera with a scanning mirror

In the remote sensing camera of a satellite, its scanning mirror always bring the different rates image motion, which will make distribution of each point's image motion on time delayed integration (TDI) CCD non-uniform. The distribution changes with angles of mirror, and it makes compensation for image motion difficult and effect of photograph un-satisfactory. For analyzing this situation, model of camera's image motion vector with a scanning mirror is built. By concreting parameters, values of image motion and drift angles of each point on CCD with different angles of mirror are gained. When central point of CCD's image motion is chosen as the standard of compensation, after compensation, if image motion value around all parts of CCD is below 1/3 pixel, the compensation is effective. With different angles of mirror, this effect of compensation is different. By analysis, when the angle of mirror is within the scope of (-20°, -0.12°) and (0.17°, 20°), photos' effect would be dim. This effect is satisfactory when angles of mirror are within the scope of (20°, 35°) (-35°, -20°) and (-0.12°, 0.17°). When angle of mirror is 0, this effect is satisfactory, and control precision of mirror's angle should be within the scope of (-0.12°, 0.17°). All of this study above can offer some reference for design of image stabilization mechanism.