The following message was quoted from http://mrl.nyu.edu/projects/autostereo/
[quote]
In order to present a stereo 3D image, each eye must see a different perspective rendered on the display corresponding to its position in space. The computer must know the position of each eye to accurately render the correct views. A parallax barrier 2-4" in front of the screen separates the views so that each alternating stripe is seen by a different eye. Note that the system can account for changes in the viewers position and orientation by changing its pitch. The barrier is dynamic - moving quickly over three phases so that it won't be perceived by the viewer. It rapidly cycles through 3 different positions (phases)  - at the end of the cycle each eye has seen every pixel on the screen, but different pixels at each phase. The use of 3 phases also allows us to separate the stripes by black spaces which allows for some registration errors in the system. [/quote]
What I did not understand is that why some of the pattern are overlapping each other while cycles through 3 different phases.
I want to understand it (before I create one). Is there any movie should the real device and what it look like when it is in operation?