Non-Null Interferometric Test of X-Ray Cylindrical Reflect Mirror

In this paper, a non-null interferometric measurement method of X-ray mirror is proposed, which can achieve high precision interferometric measurement of zero ratrace error without splicing. A high precision plane mirror is used to calibrate the ratrace error of the interference system in the full field of view. By dividing the aspherical mirror into several sub-apertures, each sub-aperture can be approximately regarded as a plane, so that the ratrace error corresponding to the sub-aperture can be found from the calibration database, and the ratrace error of the entire aspherical mirror can be obtained by simple matrix splicing. Taking the X-ray elliptic cylindrical mirror as an example, the ratrace error of the non-null interferometric surface shape of the X-ray elliptic cylindrical mirror is effectively calibrated. Compared with the splicing interferometric method, the results of the two methods are consistent, which confirms the correctness of the proposed method.

Automated summary

This paper proposes a non-null interferometric measurement method for X-ray mirrors, which achieves high-precision interferometric measurement of zero ratrace error without splicing. By dividing the aspherical mirror and using a high-precision plane mirror for calibration, the ratrace error can be accurately determined and the overall aspherical mirror error can be obtained through matrix splicing. The method is validated using an example of X-ray elliptic cylindrical mirror.