用于空间太阳望远镜的双波段极紫外反射镜  

Two-band EUV multilayer mirror used for the space solar telescope

作　　者：刘震[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所、光学系统先进制造技术重点实验室,吉林长春130033

出　　处：《光电子．激光》2014年第7期1298-1302,共5页Journal of Optoelectronics·Laser

基　　金：国家自然科学基金(60478035)资助项目

摘　　要：Fe-IX/X(λ=17.1nm)和He-II(λ=30.4nm)是太阳辐射的两条重要谱线,极紫外(EUV)空间太阳望远镜通常选择这两条谱线对日冕进行观测。为了实现在同一块反射镜对上述两条谱线同时具有较高的反射率,设计了多层膜膜系结构。首先根据极紫外波段选材原则选择了Si、B4C和Mo 3种材料,构成B4C/Si和Mo/Si叠加的两种周期结构,优化其周期数、膜层厚度等,计算了反射率曲线,并从理论验证了其可行性;然后利用磁控溅射镀膜机,在Si片上镀制了多层膜;最后用激光等离子体反射率计检测了样片的反射率,结果显示,在波长17.1nm和30.4nm处的反射率分别达到19.9%和20.2%。通过选择不同滤光片,如Mg、Al/Zr滤光片,可以获得17.1nm或30.4nm单一谱线的反射,实现了设计目标。The extreme ultraviolet （EUV） solar telescope is one of the most important instr uments to observe the solar dynamics. Fe-IX/X （λ=17.1nm） and He-II （λ=30.4nm） are fundamental spectral lines to the research of solar corona and are always be chosen by the EUV normal incidence solar telescope.A kind of mult ilayer was designed in order to realize reflecting 17.1nm and 30.4nm spectral at one mirror.According to the chosen principle of the EUV band,three materials,namely Si,B4C and Mo,are chosen to form two superposed perio d multilayers.The number of the periods and film thickness are optimized.The reflectivity of the optimized mul tilayer is calculated by computer.The feasibility of reflecting 17.1nm and 30. 4nm at one mirror has been proved in theory.The multilayer is deposited on silicon slice by magnetron sputtering coating machine.The mult ilayer is measured by laser-plasma reflectometer.The results show that the reflectivities of the mul tilayer at 17.1nm and 30.4nm are 19.9% and 20.2%,respectively.Using correct filter,such as Mg filter or Zr filt er,can reflect the single spectral line at 17.1nm or 30.4nm.

关 键 词：极紫外(EUV) 双波段多层膜 太阳望远镜 反射率 磁控溅射 

分 类 号：O434.1[机械工程—光学工程]