随着同步辐射光源和自由电子激光器相关技术的发展和光束质量的提升，对用于转递和聚焦光束能量的X光反射镜的指标要求也逐渐提高。为避免引入额外的波前误差，反射镜面形高度误差均方根值的要求已逼近至亚纳米量级。如此苛刻的面形要求对X光反射镜的测量工作带来了极大的困难和挑战。除了在各国同步辐射光源得到广泛使用的长程轮廓仪等基于角度测量的轮廓扫描仪器之外，基于激光干涉仪的拼接干涉技术也发展为测量同步辐射镜的一种有效手段。文中主要介绍了近期笔者等为测量X光反射镜而开发的拼接干涉平台。利用这一测量平台，研究了在不同的拼接参数下的多种拼接模式。着重讲述了其中纯软件拼接模式的基本原理和实际测量。用实测结果与不同测量仪器和不同研究机构的结果进行比对，验证了拼接干涉测量用于检测同步辐射镜的有效性，并展示了此拼接平台的测量表现。根据所得的测量数据看来，使用纯软件拼接模式来测量X光平面反射镜时，测量重复性的均方差值可以达到0.1 nm左右；而测量X光双曲柱面镜时（曲率半径的变化范围为50~130 m），测量重复性的均方差值为0.2~0.3 nm。此结果基本满足平面和接近平面（曲率半径大于50 m）的同步辐射镜常规检测和为确定性加工提供面形反馈的需要。

With the quick development and progress of the synchrotron radiation and free electron laser facilities, the figure error requirement for X-ray delivering and focusing mirrors is getting higher. To preserve the wave-front without introducing additional wave-front error, the mirror surface figure error is typically specified approaching the sub-nm root mean square level. This kind of ultimate specification challenges the X-ray mirror metrology and inspection. In addition to the profile scanners based on the angular measurement, such as the long trace profilometer, which have been widely used in the synchrotron light source in various countries, stitching interferometry has also been developed as an effective method for synchrotron mirror metrology. In this work, the dedicated stitching metrology platform for X-ray mirror metrology was developed. Several stitching methods with varying stitching parameters were investigated at the proposed stitching interferometric system. In this paper, we focused on the principle and measurements of using the software stitching mode. The measurement results were compared with those from several different instruments in different research institutions to verify the effectiveness of the stitching interferometry for the synchrotron mirror inspection and to demonstrate the performance of the stitching platform. According to the measurement data, the repeatability of measuring an X-ray flat mirror in the software stitching mode is at 0.1 nm RMS level. When measuring a curved mirror with its radius of curvature changing from 50 m to 130 m, the repeatability is around 0.2-0.3 nm RMS. Basically, it meets the requirement for the routine inspection and fabrication feedback of flat and near-flat (radius of curvature larger than 50 m) X-ray mirrors.