Test Of Asphere Of Off-Axis Three-Mirror Optical System And Adjustment

The off-axis three-mirror optical system has many advantages comparing to other types of systems, such as small volume, compact structure, unobstructed in the middle point of ray, sight and calibre can be enlarged, and extensible focus. Therefore, this system is widely applied in space remote sensing and optic lithography system. Accordingly, the adjustment for the asphere, especially the convex asphere and off-axis three-mirror optical system becomes more important.The main content of this paper is to conclude the theory of testing for off-axis three-mirror optical system of asphere, and how to calculate the initial structure of compensable lens for the test. Then, finally, expounding the feasibility of instead the second mirror with sphere mirror for simplifying the procedures of adjustment.