A three-dimensional rendering device may project an image on a movable
display through a collimating device, which collimates the rays from the
display into a narrow solid angle. The narrow solid angle may allow the
rays from the display to be projected only to a viewer located at a
particular position relative to the display. As the display moves, the
information displayed may change to be that appropriate for the
particular position, so that a three-dimensional image of the object may
be perceived by the viewer as the viewer changes positions around the
three-dimensional rendering device.