离焦和球差效应对高分辨率电镜性能参数的影响

Effect of defocus and sphere deviation impacting upon high-resolution electron microscope performance index

从离焦效应和球差效应出发,分析了它们对高分辨率电子显微镜分辨率和通带宽度的影响,得出了最佳欠焦量下分辨率与球差系数和电子波长的关系.在最佳欠焦条件下,分辩率与球差系数的-14次方成正比,通带宽度随欠焦量绝对值的增大而减小.4次方成正比。

In this paper,we analyze the influence of high-resolution electron microscope and band width depending on defocus and sphere deviation effect,and derive expression of relation for resolution and sphere deviation coefficient and electron wavelength when underfocus quantiy is optimal.With the optimal underfocus,the resolution is proportional to -14 exponent of sphere deviation coefficient and -34 exponent of electron wavelength.Band width decreases with increasing absolute value of underfocus.