Abstract
Electron micrographs of large biological structures show a great wealth of detail. It is somewhat disappointing to discover that details in the two-dimensional image are not easily related to the detailed arrangement of matter in the three-dimensional structure. For this a three-dimensional image is needed. It is not necessary, however, to have a holographic microscope to obtain a three-dimensional image for such an image can be reconstructed from electron micrographs obtained with a conventional electron microscope.