Abstract: A novel aspheric surface machining method, elastic deformation molding method, is proposed. Based on the linear elasticity of optical glass and the optical replication mechanism, the new method can convert complicate aspheric surface machining to simply flat surface machining, which is suitable for the machining of thin aspherical component with large curvature radius. The basic principle of the new method is described. Then taking a paraboloid with a diameter of 40 mm and a curvature radius of 2 500 mm as the target machining profile, the minimum material removal depth of workpiece that ensures the close attachment between workpiece and mold is determined by finite element simulation. The material removal model of the proposed method is established and the machining time is calculated. A machining experiment is then carried out on a built elastic deformation molding machining system, and the validation of established material removal model is verified. A parabolic surface with form accuracy of PV 0.62 μm is obtained. The influencing factors of machining form accuracy are analyzed and measures to improve the machining form accuracy in the future work are put forward.

Key words: Elastic deformation molding, Form error analysis, Plane lapping, Thin aspherical surface