Persistence of Vision
ADDPMP699
Natural occurrences and applications of persistence of vision include:
● Sparkler’s Trail Effect: the apparant line of light behind a fast-moving luminous object, commonly experienced following the use of sparklers. The effect has occasionally been applied in the arts by writing or drawing with a light source recorded by a camera with a long exposure time.
● Colour-Top/Newton Disc: colours on spinning tops or rotating wheels mix together if the motion is too fast to register the details. A coloured dot then appears as a circle and one line can make the whole surface appear in one uniform hue. The Newton disc optically mixes wedges of Isaac Newton’s primary colours into one (off-)white surface when it spins fast.
● Thaumatrope: an optical toy with a disc. The pictures on either side of a twirling disc seem to blend together into one image.
● Kaleidoscopic Colour-Top: a top on which two small discs are placed, usually one with colours and a black one with cut-out patterns. When the discs spin and the top disc is retarded into regular jerky motions, the toy exhibits forms which are similar to those of the kaleidoscope with multiplied colours.
● Rubber Pencil Trick: a pencil or another rigid straight line can appear as bending and becoming rubbery when it is wiggled fast enough between fingers or otherwise undergoing rigid motion. This effect is widely known as an entertaining magic trick for children. However, persistence of vision has been disregarded as the sole cause of the illusion. It is thought that the eye movements of the observer fail to track the motions of features of the object.
● LED POV Displays: LED display devices compose images by displaying one spatial portion at a time in rapid succession. A two-dimensional POV display is often accomplished by means of rapidly moving a single row of LEDs along a linear or circular path. The effect is that the image is perceived as a whole by the viewer as long as the entire path is completed during the visual persistence time of the human eye. A further effect is often to give the illusion of the image floating in mid-air. Early descriptions of the illusion often attributed the effect purely to the physiology of the eye, particularly to that of the retina. Nerves and parts of the brain later became accepted as important factors.













































































































































































































































































































































































































































































































































































































































































































































































































































