The development of the lens system in the Hitachi electron microscope
Astigmatism was already mentioned in Ardenne’s famous book (1), but the astigmatism described therein was one of the Seidel’s aberrations of the third order and a field aberration. Axial astigmatism was more important, though it had not been well known at that time. We usually took underfocused micrographs, in which the astigmatic image defect was vague.
Unable to display preview. Download preview PDF.
- 2.Katagiri, S., and B. Tadano: Measurement of astigmatic difference, Report of the Cooperative Research Committee on Electronmicroscopy of Japan, No. 54-A-2 (1950).Google Scholar
- 4.Leisegang, S.: Optik 11, 49 (1954).Google Scholar
- 6.Watanabe, H., and N. Morito: Optik 12, 166 (1955).Google Scholar