Apparent Motions in Three-Dimensional Images

Abstract

Apparent motions rank among the most interesting and conspicuous optical illusions. They have enabled psychologists to gain valuable insights into the mechanism of vision, although to people not familiar with such phenomena they appear spectacular and sometimes even terrifying. Completely solid objects seem to deform and penetrate each other, images follow the observer’s changing points of view and motions appear to be falsified and even reversed. Such impressions are, of course, entertaining and it is for this reason that the most widely known apparent motion, the cinema film, has become particularly popular. Motion pictures are successively shown static images of instantaneous stages of motion which appear to fuse into continuous motion.