A popular belief during the late 19th and early 20th century held that the image of the last thing seen at the moment of death remained imprinted forever upon the retina of the eye. It was called an “optogram.” This belief developed concurrently with rapid advances made in photography during the historical period, and was seemingly validated by certain scientific experiments in ocular physiology done in the 1870s. Looking for the “photo in a dead person’s eye” soon became an accepted police investigative procedure and an established touchstone of much turn-of-the-century SF and detective fiction. In later 20th century literature and film, a modern variant of the optogrammic photo emerged: the dead brain itself was now “read” using high-tech scanners to record the deceased’s final vision (or thoughts) before death occurred. The goal of this article is to examine this pseudoscientific literary motif, its origins and evolution, and to show how science fact can sometimes become science fiction and take on a life of its own in the popular imagination.
Arthur B. Evans. "Optograms and Fiction: Photo in a Dead Man's Eye." Science Fiction Studies 20.3 (1993): 341-361. Available at: http://scholarship.depauw.edu/mlang_facpubs/9/