Free-form surface reconstruction of off-axis three mirror optical system based on rhino

Abstract

With the development of modern space optical system, off-axis reflective system with wide spectrum, high resolution and large field of view has become the main direction of optical design. However, the off-axis property of off-axis reflective structure brings asymmetric aberration, which makes designers use free-form surface frequently to correct the aberration of optical system and improve the imaging quality. When the Trace Pro optical mechanical simulation software cannot accurately convert the optical system with free-form surface in CODE V, it is difficult to simulation stray light and analysis environmental in the subsequent studies. The reconstruction of free-form surface of off-axis three mirror optical systems are realized by Rhino in this paper. For the free-form surface in the off-axis three mirror optical systems designed by CODE V, a uniform circular dot ring array sampling method based on polar coordinates is proposed to obtain the free-form surface point cloud data. The point deviation of 5mm-80mm was analyzed, and the optimal sampling interval for the point cloud data of XY polynomial free-form surface with an aperture of 150mm was determined to be 10mm; The NURBS method is used to reconstruct the free-form surface model in Rhino, and the free-form surface reconstruction of the off-axis three mirror optical system is modeled in Trace Pro. Through the simulation of imaging optical path and the analysis of image point dispersion spot radius, it is verified that the free-form surface model of off-axis three mirror optical system can be reconstructed based on rhino. This research provides an effective method reference for optical mechanical joint simulation analysis.