13.5nm Schwarzschild显微镜系统及成像实验  

13.5 nm Schwarzschild microscope and imaging experiment

作　　者：王新[1,2,3] 穆宝忠[1,2] 黄怡[1,2] 朱京涛[1,2] 王占山[1,2] 贺鹏飞[3] 

机构地区：[1]同济大学精密光学工程技术研究所物理系,上海200092 [2]同济大学上海市特殊人工微结构材料与技术重点实验室,上海200092 [3]同济大学航空航天与力学学院,上海200092

出　　处：《光学精密工程》2011年第8期1709-1715,共7页Optics and Precision Engineering

基　　金：国家自然科学基金资助项目(No.10825521);上海市科学技术委员会科研计划资助项目(No.0952nm06900);国家科技合作项目(No.2008DFA01920)

摘　　要：研制了工作波长为13.5 nm的Schwarzschild成像显微镜。从共轴两镜系统的基本理论出发,通过消除三级球差、彗差和像散设计了Schwarzschild物镜的光学初始结构,计算了物镜的光学传递函数。结果表明,物镜在±0.3 mm视场内像方空间分辨率可达550 lp/mm。根据工作波长和镜面的入射角度设计了Mo/Si周期多层膜反射镜,制作了Schwarzschild显微镜光学元件,多层膜元件对13.5 nm波长的反射率为61%。为了消除可见光和紫外光对系统成像的影响,设计并制备了材料为Zr,Si和Si3N4的滤波片,该滤波片在13.5 nm处的透过率为21.1%。利用激光等离子体光源对60 lp/mm网格进行了成像实验,结果表明,系统在0.5 mm视场内的分辨率优于3μm,结论认为CCD探测器分辨率极限是影响成像实验分辨率的主要因素。A Schwarzschild microscope working at 13.5 nm was developed.According to the theory of a coaxial two-mirror system,the optical structure of Schwarzschild objective was designed by eliminating third-order spherical aberrations,coma and astigmatism.Experiments show that the spatial resolution of the designed objective achieves 550 lp/mm within the field of ±0.3 mm with respect to the calculation of modulation transfer function.Based on the working wavelength and incidence angle of lights,the Mo/Si multilayer optics with the reflectivity of 61% at 13.5 nm was designed and fabricated.In order to remove visible and ultraviolet lights,a filter with materials of Zr,Si and Si3N4 was designed and fabricated,and the transmittance of 21.1% was obtained at 13.5 nm.With the purpose of demonstrating the resolution of microscope,the 60 lp/mm grid backlit by laser produced plasma was imaged via the Schwarzschild microscope on a Charge Coupled Device（CCD）,and the results show that the imaging system can offer the resolution of 3 μm in the 0.5 mm field.It concludes that the resolution of imaging experiment is limited by the resolution of CCD camera.

关 键 词：成像系统 Schwarzschild成像显微镜 MO/SI多层膜 滤波片 空间分辨率 

分 类 号：TH742.6[机械工程—光学工程]