Test Of Optical Surface Error With Variable Aberration Compensation

Aspherical optics with high precision is widely utilized in modern optical systems,whose manufacture heavily depends on optical surface figure metrology with higher accuracy.Along with the innovation of machining methods and update in machining facilities,a number of testing issues emerge.Two issues are studied in this thesis,namely,unique application of a certain null-optics and testing of topical flaws.Feasible solutions are proposed.As for the first issue,a variable optical null(VON)using a high-order even aspherical(HOEA)singlet is designed and optimized based on characteristic of HOEA surfaces.Its large compensating range is verified by a series of aspherical optics,including two different elliptical surfaces with an aperture of 326 mm.As for the testing topical flaws issues,dynamitic null using spatial light modulation is studied.Preliminary experiments are conducted,and considerations for further studies are proposed.This thesis comprises three parts of contents:1.Study on variable aberration characteristics of HOEA singlet.Geometrical and optical characteristics of HOEA are analyzed in view of geometry.Influences of high order terms and axial distances on variable aberration are also studied.Simulations verify the capacity of the VON,and the compensation range is visually demonstrated.2.Study on variable aberration system.Parameters of the VON are designed and optimized to test a series of aspherical optics.For tackling the problem of limited aperture,high slope and large asphericity of the HOEA singlet,methods of machining and testing basing on deterministic figuring and annular sub-aperture stitching are adopted,which leads to accuracy of better than 0.5 ? Peak to Valley(PV)of high order aspherical surface and 0.08 ?(PV)of flat surface.Two different elliptical surfaces with an aperture of 326 mm are used to verify capacity of the VON.3.Study of dynamic null using a spatial light modulation.Phase VS gray modulation character is studied on the premise of working principles.Surface error calibration method of a particular spatial light modulation,named LC2012,is analyzed.Accuracy of aberration simulating and dynamic aberration are verified,and preliminary experiments are conducted for flaw testing.