QUANTITATIVE DIFFRACTOMETRY AT 0.1 NM RESOLUTION FOR TESTING LENSES AND RECORDING MEDIA OF A HIGH-VOLTAGE ATOMIC-RESOLUTION MICROSCOPE

Amorphous Ge thin foils are used to determine the optical parameters, especially the contrast transfer envelopes, of the 1250 kV atomic reso lution microscope JEM ARM1250. The use of such foils to check the info rmation limit near 0.1 nm is accompanied by fundamental problems. The weak phase object approximation is about to fail and the superposition of five independent contrast damping effects requires careful correct ion procedures to be applied. It is described how far digital image pr ocessing of numerically Fourier transformed images of amorphous object s can go. The alternative use of laser diffractograms is critically an alysed in a comparative study. Finally, images at different magnificat ions are used to check the properties of high-voltage recording media, such as film, slow scan CCD camera and Imaging Plate.