Research on wavefront fitting and reconstruction for annulus-sector segmented primary mirror

Using finite element analysis, thermal deformation data of annulus-sector segmented primary mirror are obtained. Zernike circular polynomials and Zernike annulus-sector polynomials are used to fit the discrete date respectively. Then the fitting precision is compared. Based on Hartmann-Shark wavefront sensor, modal wavefront reconstruction of distorted wavefront induced by thermal deformation mirror is realized. Using two different polynomials before-mentioned, influences of the condition number and measurement error on reconstruction precision are discussed.