Design And Tolerance Analysis Of Large Aperture Optical Systems

With the development of science and technology,the requirements for imaging quality of optical systems are becoming stricter,and the demand for high-resolution optical imaging systems is becoming more urgent.With the advent of high-resolution optical systems,the aperture of optical systems has also increased,and large-diameter optical systems will be the development trend of remote sensing technology.In 2018,the Changchun Optical Machine of the Chinese Academy of Sciences designed a silicon carbide(SiC)monomer aspherical mirror with a diameter of D=4.03 m,which is the world's leading level.If the mirror is used for remote sensing satellite imaging,it is due to its size,weight and Cost constraints are difficult to achieve at the current state of the art.Therefore,if you want to further increase the diameter of the optical system,you need to use the form of the main mirror.At present,the typical remote sensing optical systems of main mirror splicing include: 6.5m JWST(James Webb Space Telescope)main mirror reflex telescope represented by James Webb and 20 m film diffraction main representative represented by MOIRE(Membrane Optical Imager Real-time Exploitation)mirror telescope.The purpose of this paper is to design a three-reflection optical system with 4m,6.5m,and 9m apertures and a thin film diffractive optical system(single,double,and triple),and to splicing the reflective primary and thin film diffraction primary mirrors using Zemax software.Finally,the tolerances of large aperture optical main mirrors(including integral aperture mirrors,integral aperture film lenses,spliced mirror mirrors,spliced mirror film lenses)were analyzed,and the tolerances of large aperture optical systems were analyzed.The research results can provide reference for the engineering research of large-caliber optical systems.Firstly,a brief analysis of the advantages of using a coaxial three-reflection optical system compared to a coaxial two-reflective and coaxial four-reflective type and the advantages of using a thin film diffractive lens over a conventional refractive lens,and the imaging principle of the coaxial three-reflection optical system and the imaging principle of the single-layer,double-layer and three-layer film primary mirror optical systems are analyzed.Then,according to the imaging principle of the coaxial three-reflection optical system,the overall aperture and splicing overall aperture three-reflection optical system of 4m,6.5m and 9m are designed respectively.According to the imaging principle of the film main mirror optical system.Single-layer,double-layer,and three-layer film primary mirror optical systems with overall aperture and splicing of overall aperture,and in a non-sequence mode,small mirrors are used to splicing the main mirrors of the coaxial three-reflection optical system and the thin film diffraction imaging system.Finally,the tolerances of the main mirror and optical system of the coaxial three-reflection optical system were analyzed.The tolerances of the main mirror and optical system of the single-layer,double-layer and three-layer main mirror optical systems of the thin film diffraction main mirror were analyzed,and the tolerance analysis of the spliced reflective primary mirror and the thin film diffraction primary mirror sub-mirror is performed in non-sequence mode.