The dynamic interferometry technology of 4.5-meter concave aspherical mirror and relativity precision analysis

The dynamic interferometry is used to overcome the problem of the vibration and the air turbulence present in the testing process of concave aspherical mirror, whose aperture is extra large, and optical path is extra long. Aiming to 4.5m aperture concave mirror, two schemes have been designed: offner refractive and reflective compensators. The analytical model of the theoretical error analysis under the dynamic interferometry condition has been built. According to the result we can come to a conclusion that using the method of dynamic interferometry, the accuracy of measuring can be reached within λ/80. The optical testing path of mirror with multiple segments has been designed in the end. Results of this paper could provide references for the design, processing, assembling and testing technologies of large or extra large optical system.