中文摘要：

在XiaominTong等的理论上发展了一个二维理论模型，建立散射光强分布与超光滑表面功率谱密度（PSD）的关系。在上海同步辐射光源小角散射实验站上，用不同粗糙度的210mm和320mm长的超光滑反射镜进行掠入射X射线散射法（GIXRS）实验，测量散射分布并进行处理，计算出两块反射镜的表面均方根粗糙度（RMS）。与白光干涉法测量结果的比对结果表明，根据这种理论进行数据处理得到的RMS值，与白光干涉法的测量结果非常符合。

英文摘要：

In this work, surface roughness of two large-size super-smooth mirrors, of 210 and 320 mm in length, was studied by grazing incidence X-ray scattering method （GIXRS）. A two-dimensional theoretical model was derived based on Tong＇s result in 1993, so as to the correlate power spectrum density （PSD） of a mirror surface to the intensity distribution of X-ray scattering. The two mirrors were measured on Beamline 16B at Shanghai Synchrotron Radiation Facility and the data were analyzed. The results showed that the root mean square of the surface roughness calculated using the model agreed well with that measured by a white-light 3D profiler.