The observation of scan electronlens shown that the result, the foam has the ideal structure.
扫描电镜的观察结果表明，研制的泡沫具有比较理想的泡孔结构。
2
Use magnetic field lens again, two kinds of electronlens elaborate respectively below form and principle.
又用磁场透镜，下面分别阐述两种电子透镜的构成和原理。
3
By assuming the weak lens focal length expression to be the first term in a power series a simple and accurate formula can be derived for the objective focal length of a magnetic electronlens.