Turning Shadow
Floor 1 | Mindscapes
A shadow of a rotating cube is viewed on a ground glass screen using Pulfrich glasses. These are glasses with one eye opening open and the other with a grey filter. The eye that looks through the dark filter receives less light than the open eye - its retina therefore sends the nerve impulses to the brain a little later than the open eye. This minute time difference is interpreted in the brain to form what appears to be a three-dimensional cube. This phenomenon is called the Pulfrich phenomenon.
