Optical Toys

The Phenakistoscope

Today I visited a cool site that exhibited optical toys. My favourite optical Toy was the Phenakistoscope. "The phenakistoscope uses the persistence of motion principle to create an illusion of motion. Although this principle had been recognized by the Greek mathematician Euclid and later in experiments by Newton, it was not until 1829 that this principle became firmly established by Joseph Plateau.

The phenakistoscope consisted of two discs mounted on the same axis. The first disc had slots around the edge, and the second contained drawings of successive action, drawn around the disc in concentric circles. Unlike Faraday's Wheel, whose pair of discs spun in opposite directions, a phenakistoscope's discs spin together in the same direction. When viewed in a mirror through the first disc's slots, the pictures on the second disc will appear to move. "- Nov 11 2009,courses.ncssm