Chapter 1 Introduction to Stereo Imaging

Abstract

This chapter presents an introduction to stereo imaging. The extremely high resolving power of the electron microscope has greatly advanced the study and understanding of biological systems. The transmission electron microscope produces a projection image of the object that contains only two-dimensional information. This image is a faithful representation of the object only if the specimen is assumed to be infinitely thin. It is found that as this condition does not apply to a real specimen, a sufficient approximation is obtained if the sample is thin compared with the dimensions of the details under study. The tilting of the sample between exposures generates parallax, which is defined as the distance between two points in one micrograph minus the distance between the same two points in the second micrograph. A stereo effect is achieved when two micrographs recorded with different orientations of the specimen with respect to the electron beam are viewed simultaneously. The observed depth in a stereo image can make objects appear either to recede away from or to come up toward the observer.