The phenakistoscope used a spinning disc attached vertically to a handle. Arrayed around the disc’s center were a series of drawings showing phases of the animation, and cut through it were a series of equally spaced radial slits. The user would spin the disc and look through the moving slits at the disc’s reflection in a mirror. The scanning of the slits across the reflected images kept them from simply blurring together, so that the user would see a rapid succession of images that appeared to be a single moving picture.
Of course this is the principle which underlies all viewing of moving pictures. The next work he published on the topic of vision related to the mechanism by which eye retains an impression of a coloured object in the complementary colour.
After going to market, the phenakistoscope received other names, including Phantasmascope and Fantoscope (and phenakistiscope in Britain and many other countries). It was quite successful for two years until William George Horner invented the zoetrope, which offered two improvements on the phenakistoscope. First, the zoetrope did not require a viewing mirror. The second and most influential improvement was that more than one person could view the moving pictures at the same time.
Fascinated by the persistence of luminous impressions on the retina, he performed an experiment in which he gazed directly into the sun for 25 seconds. Consequently, he lost his eyesight later in his life. He continued his research at Ghent University as a blind person for forty years, partly inoptics. Joseph Plateau died in Ghent.
Spotter: The Richard Balzer Collection