vv2: "persistence of vision"

[s~Z]

http://www.exploratorium.edu/snacks/persistence_of_vision.html

Your eye and brain retain a visual impression for about 1/30th of a second.
(The exact time depends on the brightness of the image.) This ability to
retain an image is known as persistence of vision. As you swing the tube
from side to side, the eye is presented with a succession of narrow,
slit-shaped images. When you move the tube fast enough, your brain retains
the images long enough to build up a complete image of your surroundings.

Persistence of vision accounts for our failure to notice that a motion
picture screen is dark about half the time, and that a television image is
just one bright, fast, little dot sweeping the screen. Motion pictures show
one new frame every 1/24th of a second. Each frame is shown three times
during this period. The eye retains the image of each frame long enough to
give us the illusion of smooth motion.

http://freeweb.pdq.net/headstrong/Persist.htm

Persistence of vision has been known about for a long time, but an article
written by Roget (of Thesaurus fame) in the early 19 th century spawned
popular interest. After this many novelties and popular entertainments were
invented based on the principle. (Most with classically based names - the
Victorians felt using a Latin or Greek name gave credibility to their
inventions. This tradition of naming cinematic equipment and processes
lasted much longer; hence Technicolor, Panavision, CinemaScope, and even
television.) What follows is a brief description of the principal designs,
and notes on constructing models of them. There were many more devices
invented than those listed here, which were the major, most influential
designs.

[See the above url for the list of devices. Very Pynchonian.]