Opt Express. 2022 Dec 5;30(25):45918-45929. doi: 10.1364/OE.462784.
Deflectometric slope profiler is an essential technique for accessing the surface metrology of mirrors used in synchrotron radiation beamlines. To increase the upper spatial frequency bandwidth limits of deflectometric slope profiler, reducing the beam spot size on the mirrors is necessary. In this paper, we introduce a profiler system: the focusing long trace profiler (FLTP). It contains a newly developed optical head capable of raising upper spatial frequency bandwidth limits by using a focused beam instead of a collimated beam to scan the sample. This feature has been proven in a numerical simulation experiment, where a spatial resolution of up to around 0.05 mm was reached when the sample is set at focus plane. The system is implemented and characterized in several experiments; calibration of the focusing optical head shows that it can achieve a high angular accuracy of sub-50 nrad root-mean-square (rms) and defocusing of sample under test (SUT) has no effect on the measurement results; the measurement tests also demonstrate the system's advantage in highly curved mirror profile metrology.
掠入射斜率轮廓仪是一种用于获取同步辐射光束线中使用的反射镜表面计量学的重要技术。为了提高掠入射斜率轮廓仪的上限空间频率带宽限制，有必要减小镜面上的光束光斑尺寸。在本文中，我们介绍了一种轮廓仪系统：聚焦长程轮廓仪（FLTP）。它包含一个新开发的光学头，能够通过使用聚焦光束而不是准直光束来扫描样品，从而提高上限空间频率带宽限制。这一特性已在数值模拟实验中得到证实，当样品处于焦平面时，可达到高达约 0.05mm 的空间分辨率。该系统在多个实验中得到了实现和表征；聚焦光学头的校准表明，它可以实现亚 50nrad 均方根（rms）的高角度精度，并且测试样品的离焦对测量结果没有影响；测量测试还证明了该系统在高度弯曲的反射镜轮廓测量方面的优势。
