RESOLUTION AND OPTIMUM CONDITIONS FOR DARK-FIELD STEM AND CTEM IMAGING

被引：6

作者：

HAMMEL, M

ROSE, H

机构：

[1] Institut für Angewandte Physik der TH Darmstadt, W-6100 Darmstadt

来源：

ULTRAMICROSCOPY | 1993年 / 49卷 / 1-4期

关键词：

D O I：

10.1016/0304-3991(93)90214-I

中图分类号：

TH742 [显微镜];

学科分类号：

摘要：

Optimum values for the objective aperture angle and defocus for dark-field imaging in STEM and CTEM are calculated based on the point-scatterer approximation. The effect of chromatic and spherical aberration is taken into account. The resolution limit for the dark-field mode and several phase-contrast modes is calculated. The comparison shows that some phase-contrast imaging modes (e.g. hollow-cone illumination in CTEM and the difference signal of a ring detector configuration in the STEM) are superior in resolution power to the dark-field mode.

引用

页码：81 / 86

页数：6

共 18 条

[1]

BORN M, 1965, PRINCIPLES OPTICS

[2] IMAGE CONTRAST IN A TRANSMISSION SCANNING ELECTRON MICROSCOPE [J].