论文部分内容阅读
一、引言 电子探针仪和某些带X射线谱仪的扫描电镜,都要求物镜焦距尽可能长,以保证有足够的样品空间,设置谱仪及其操作机构;球差系数尽可能小,以提高仪器分辨率。单极靴磁透镜,在极靴口处沿轴磁通密度高,场分布的半高宽窄,因而象差系数小,焦距长,可用来作为上述仪器的小型物镜。此外,单极靴透镜也可用作微细束加工机的物镜。
I. INTRODUCTION Electron probe and some scanning electron microscopy with X-ray spectrometer require objective lens focal length as long as possible to ensure sufficient sample space to set up the spectrometer and its operating mechanism; spherical aberration coefficient as small as possible, To improve instrument resolution. The unipolar shoe magnetic lens has high magnetic flux density along the axis of the pole shoe and a half height width of the field distribution so that the aberration coefficient is small and the focal length is long, which can be used as a small objective lens of the above instrument. In addition, the monopole lens can also be used as an objective of a microbeam processing machine.