Development of an automatic electron diffraction pattern analyzing system

Abstract

The electron diffraction pattern has information on the crystal structure of samples, such as the crystal system, lattice constants and the orientation for the incident beam. Material can be identified by measuring the above characteristics and, in general principle by measuring their accurate lattice spacings. However, this measurement requires a lot of time and fundamental knowledge of the crystal structure.The present automatic analyzing system of the electron diffraction pattern makes the analysis ease. The outline of this system is described in this paper.The hardware system consists roughly of three components; a low-light-level TV device called the image carrier, a frame memory, and a minicomputer. The image carrier transforms the image formed on the flourescent screen of a transmission electron microscope (TEM) into video signals. The frame memory is provided with a memory plane of 512 x 512 pixels, each having 256 gray levels. It digitaizes video signals of the image and stores them in itself.