消除拼接主镜式望远镜的分块子镜间的共相位倾斜（tip-tilt）误差是有效提升集光能力、实现共相位成像的关键之一。提出了一种基于相位传递函数（PTF）的分块子镜的tip-tilt高精度检测方法。在分块镜的共轭面处设置具有离散孔结构的光阑，将其作为tip-tilt检测系统的入瞳，借助傅里叶分析，推导建立了误差检测系统的PTF与tip-tilt的函数关系，通过对探测得到的点扩散函数进行傅里叶分析，得到PTF，依据建立的函数关系即可实现tip-tilt的高精度检测。对所提方法进行了仿真分析和实验验证，检测精度的均方根（RMS）值为2.99×10-3λ（λ为波长）。所提方法结构简单，只需要设置一个具有离散孔结构的光阑，可用于拼接式主镜、稀疏孔径系统的共相位tip-tilt误差检测。

激光差动共焦显微镜具备高空间分辨率特点, 但因其逐点扫描成像方式, 扫描时间长, 易受三维扫描系统不稳定和环境干扰等影响, 产生系统漂移, 影响仪器的空间分辨率。利用楔块机构高稳定特点, 结合刹车机构的自由抱闸特性, 设计了一种新型的轴向升降机构, 由此构建了结构更具稳定特性的电动三维扫描系统。稳定性实验验证在搭建的激光差动共焦显微镜上进行, 经过监测系统在90min内的轴向位置, 轴向漂移小于50nm, 与原三维扫描系统漂移140nm对比, 漂移速度明显减慢, 稳定性有显著提升, 进而明显改善了差动共焦显微成像效果。

We report the laboratory experiment on a segmented mirror testbed that shows the use of a dispersed Rayleigh interferometer to phase segmented mirrors. Segment alignment of tip-tilt is fulfilled by overlapping diffraction pattern centroids of the three individual segments on the focal plane. A spherical interferometer is introduced to evaluate the performance of piston, tip-tilt sensing, and control closed-loop, and finally a total residual root-mean-square (RMS) surface error of about 45 nm is achieved, in which a typical error of about 20 nm is contributed by piston. These results demonstrate that the dispersed Rayleigh interferometer can successfully sense the piston of segmented mirrors and be used in phasing segmented telescopes under extensive studies.