1:Technology of iron polishing for astronomical mirror

   two spherical mirrors with aperture 200mm were figured by ion beam with surface accuracy less than 10nm(rms).

   two plane mirrors with aperture 100mm were figured by ion beam with surface accuracy less than 8nm(rms).

2:Technology of replication for aspherical mirror

   two ellipsoid mirrors with aperture 400mm,f/1.62 were replicated firstly in China,twice replication technology were adopted in order to solve the difficult problem for testing of master mould of convex aspherical surface.