Detection of Object Movement in the Optical Diffractograms of Electron Micrographs

original text] Detection of object movement in the optical diffractograms of electron micrographs. Movements of the objects during an electron microscopic exposure cause characteristic modulations of the Fourier transform of the photographic density distribution, from which the nature of the movements can in turn be reconstructed. Modulations of this type were observed in optical diffractograms of a number of micrographs of amorphous carbon films and could be assigned to particular movements. 1 an object, in other words, in whose phase structure all spatial frequencies are distributed with equal probability (“white scatterer”)] of the astigmatism due to the buildup of contamination, etc.). If these changes occur over a time comparable to the exposure time T, we have Here α(t) stands for a general time-dependent coordinate transformation. The recorded optical density will be proportional to (see [2])