Persistence of vision
Since its introduction, the term "persistence of vision" has often been mistaken to be the explanation for motion perception in optical toys like the phenakistiscope and the zoetrope, and later in cinema.
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.
This also happens in the case of shooting stars, whose light seems distended on account of their speed of motion, all according to the amount of perceptible distance it passes along with the sensible impression that arises in the visual faculty.
al-Haytam also noted that the top appeared motionless when spun extremely quickly "for none of its points remains fixed in the same spot for any perceptible time".
[19] Leonardo da Vinci wrote in a notebook: "Every body that moves rapidly seems to colour its path with the impression of its hue.
The truth of this proposition is seen from experience; thus when the lightning moves among dark clouds the speed of its sinuous flight makes its whole course resemble a luminous snake.
"[20] In his 1704 book Opticks, Isaac Newton (1642–1726/27) described a machine with prisms, a lens and a large moving comb with teeth causing alternating colors to be projected successively.
In 1821 the Quarterly Journal of Science, Literature, and The Arts published a "letter to the editor" with the title Account of an Optical Deception.
The letter concluded: "The general principles on which this deception is based will immediately occur to your mathematical readers, but a perfect demonstration will probably prove less easy than it appears on first sight".
Roget claimed that the illusion is due to the fact "that an impression made by a pencil of rays on the retina, if sufficiently vivid, will remain for a certain time after the cause has ceased."
[24] As a university student Joseph Plateau noticed in some of his early experiments that when looking from a small distance at two concentric cogwheels which turned fast in opposite directions, it produced the optical illusion of a motionless wheel.
On 10 December 1830, scientist Michael Faraday wrote a paper for the Journal of the Royal Institution of Great Britain, entitled On a Peculiar Class of Optical Deceptions.
He had cut concentric series of apertures nearer to the center of a disc (representing smaller cogwheels) with small differences in the amount of "cogs" per "wheel".
In July 1832 Plateau sent a letter to Faraday and added an experimental circle with apparently abstract figures that produced a "completely immobile image of a little, perfectly regular horse" when rotated in front of a mirror.
[30][31] After several attempts and many difficulties Plateau managed to animate the figures between the slits in a disc when he constructed the first effective model of the phénakisticope in November or December 1832 .
[6] In January 1834, William George Horner also suggested a cylindrical variation of Plateau's phénakisticope, but he did not manage to publish a working version.
[33] William Ensign Lincoln invented the definitive zoetrope with exchangeable animation strips in 1865 and had it published by Milton Bradley and Co. in December 1866.
[34] In his 1833 patent and his explanatory pamphlet for his stroboscopic discs, Simon Stampfer emphasized the importance of the interruptions of the beams of light reflected by the drawings, while a mechanism would transport the images past the eyes at an appropriate speed.
[6] The idea that the motion effects in so-called "optical toys", like the phénakisticope and the zoetrope, may be caused by images lingering on the retina was questioned in an 1868 article by William Benjamin Carpenter.
At higher speeds, when test subjects believed to see both positions more or less simultaneously, a moving objectless phenomenon was seen between and around the projected figures.
[citation needed] When contrasting the theory of persistence of vision with that of phi phenomena, an understanding emerges that the eye is not a camera and does not see in frames per second.
In other words, vision is not as simple as light registering on a medium since the brain has to make sense of the visual data the eye provides and construct a coherent picture of reality.
