宽视场长焦距离轴三反射镜光学系统的设计

分析了离轴三反射镜系统成像特性．根据共轴三反射镜光学系统像差理论，确定结构参数的基本计算公式．设计了长焦宽视场的离轴三反射镜光学系统，分析了系统结构参量对像差的影响．结果表明，该系统视角较大，地面复益范围较宽，成像质量接近衍射极限．     

Magnetic properties of oxides and silicon single crystals

The magnetic properties of single crystals Si, SrTiO₃, LaAlO₃, MgO, and (La,Sr)(Al,Ta)O₃ were investigated systematically. Three origins of the magnetizations of these crystals, namely, an intrinsic diamagnetic, a paramagnetic, and a ferromagnetic contribution, have been found to influence the magnetic signals measured on the crystals, in some important application scenarios such crystals being served as substrates with the magnetic thin film epitaxially grown on. Quantitative analyses methodologies were developed and thorough investigations were performed on the crystals with the intrinsic materials parameters thus revealed, especially that the intrinsic diamagnetic susceptibility differential dχ_dia/dT were identified quantitatively for the first time in SrTiO₃, LaAlO₃, MgO, and (La,Sr)(Al,Ta)O₃. The paramagnetic contribution is found to be the key in terms of the magnetic properties of the crystals, which in turn is in fact a consequence of the 3d impurities doping inside the crystal. All the intrinsic materials parameters are given in this paper as datasets, the datasets are openly available at https://www.doi.org/10.57760/sciencedb.j00113.00028.     

纳米尺度延性域干切削KDP晶体的无粘屑研究

为了避免使用切削液及其相应清洗工艺对KDP晶体表面产生雾化、引入杂质等降低晶体抗激光损伤阈值的不利因素,采用干切削技术对KDP晶体进行超精密切削。在干切削KDP晶体工艺中所遇到的难点是切削屑片易粘附已加工表面,由此产生屑片粘附点难清洗、易雾化等问题。本文提出了基于真空抽屑装置干切削KDP晶体的新工艺,重点解决了干切削工艺下KDP晶体表面粘屑现象,实现了无需清洗、无杂质的加工表面。在选择延性域切削参数条件下,取得了表面粗糙度为2.69 nm(Ra)的无粘屑、超光滑表面。     

基于螺旋刻划方法的KDP晶体临界切削厚度研究

为了取得贴近切削加工的临界切削厚度,本文提出了一种采用金刚石刀具对KDP晶体进行螺旋刻划、基于所得刻槽微观形貌特征参数计算临界切削厚度的新方法;分析了切削速度和材料各向异性对临界切削厚度的影响;通过切削实验验证所得临界切削厚度.结果表明,晶体材料的各向异性对临界切削厚度有显著影响;在低速切削范围内,切削速度对临界切削厚度影响不显著;基于所得临界切削厚度选择切削参数,实现了KDP晶体全晶向延性域切削,取得了表面粗糙度为2.57 nm(Ra)的超光滑表面.