The birefringent lens, consisting of a piece of birefringent crystal and a piece of optical glass, is a key component in the dual focus interference microscope. 双焦点(DF)干涉显微镜因其高稳定性和高分辨率的特点而受到重视,其核心元件双折射透镜由一片双折射晶体和一片光学玻璃胶合而成。
Focal Shift and Focal Switch of Partially Coherent Light in Dual Focus(DF) Systems 部分相干光在双焦聚焦系统中的焦移和焦开关
The ellipsoid lens antenna in this paper is different from lens antenna and rotating dish antenna, it has dual focus structure, can focus the energy from one focusing point to another focusing point. 本课题所研究的椭球天线不同于透镜天线、旋转抛物面天线等,它具有双焦点(DF)结构,能够将来自一点的能量聚焦于另一点。
Reform of dual statuses and dual functions : the focus of institutional reform of government 双重身份和双重职能的改革应是政府体制改革的重点
The factors that effect the measuring accuracy of dual star point fixed focus measuring method for minimun focal length of plane optical element is analyzed. Some problems which should be given attention to in test are pointed out. 分析用双星点定焦法测量平面光学元件最小焦距时影响测量精度的因素,指出测量中应注意的问题。