THE MAGIC EYE  INTRODUCTION
When you watch MAGIC EYE pictures you can recognize behind (or in front) of the screen
3D objects, which are encoded in the pictures or which can directly be seen.
In order to learn the technique of 3D viewing you should start with pictures where the
3D objects are not encoded (see the aquarium). All the other pictures are with encoded
3D objects and it is more difficult to recocnize the 3D objects in those pictures.
This is how 3D viewing works:
3D pictures are almost periodical in horizontal direction.
The point of the intersection of the line 'left eye  point of the picture' with the
line 'right eye  point of the picture of the next period' is the appropriate point of
the 3D object. That means 3D viewing works only with two eyes. A straight line through
the left eye and the right eye must be parallel to the horizontal direction of the picture.
Because the 3D picture is not exactly periodical it is possible to see structures in 3D.
If the period has a high value the 3D object is faraway, if the period has a small value
the 3D object is close to the viewer.
In order to get the best results in 3D viewing note this:
 Avoid light reflections on the screen (best viewed in a dark room)
 Hold your head straight
 The distance to the screen should be about 80 cm
 Try to interfere points of neighboring periods by watching the picture 'blurred'
And here a little bit more precise for the friends of mathematics:
 zaxis
/\
eye 1  eye 2
O  O
*  *
*  *
*  *
* *
* 
* *
* *  3D picture
XX>
* *  (screen) xaxis
X 
3D object 

If the position of eye 1 is (x_{1}, 0, z_{1}),
the position of eye 2 is (x_{2}, 0, z_{2}) =
(x_{1}, 0, z_{1})
and the position of the 3D object is (x_{3}, y_{3}, z_{3})
then the appropriate positions in the 3D picture are (x_{1}', y_{1}', z_{1}')
and (x_{2}', y_{2}', z_{2}'), respectively:
x_{1}'=(z_{1}x_{3}z_{3}x_{1})/(z_{1}z_{3}),
x_{2}'=(z_{1}x_{3}+z_{3}x_{1})/(z_{1}z_{3}),
y_{1}'=y_{2}'=(z_{1}y_{3})/(z_{1}z_{3}) and
z_{1}'=z_{2}'=0.
And here is a little program (Turbo Pascal source code) about that.
(c) Lutz Tautenhahn 1/99
go to the pictures