Saccade Art Example
This web page hosts a Java applet that
demonstrates "saccade art."
The applet renders a collection of narrow vertical
strips of light on a black background. The
pattern of colors within each of the strips
is changed rapidly by the computer. If the viewer allows her
eyes to follow the apparent left-to-right
movement, then a more filled-in image becomes
"painted" on the her retina and the moving objects
The speed of motion of the objects is limited by
two factors: the speed of your computer and a
built-in delay factor. The effect is stronger if
viewed in a dark room with a good, bright monitor.
Saccade art is a good example of a stimulus
that creates a 2D image nowhere but in the
cooperative observer's eye.
An excellent exhibit demonstrating this effect
resides at San Francisco's Exploratorium. The exhibit
uses several linear light arrays instead of a computer screen,
and these light arrays are mounted high up on a wall.
An animated program lasting several minutes is presented
there with the technique in which a variety of shapes move in
left-to-right, right-to-left, and even both directions
(This applet Created by Steve Tanimoto, 22 March 2006)
Due to more stringent Java security, it has become difficult to run applets on the
web. Consequently, I have created a downloadable application, packaged in a Java .jar file.
It's available via the link on the previous page. To use it, unzip the zip file,
and double-click on the .jar file. If Java is correctly configured, you should be
able to run the demo. Try varying the number of columns of pixels displayed in order to
find out what it's like to barely see the patterns when the number of columns is low.
I might help to use a large display in a dark room and to move your head and/or eyes left and right.