The inclusion of animation in holographic stereograms introduces errors in the perceived location of moving objects. Consider, for example, a hologram of a road with a moving car. When each view of this hologram is recorded the car is in a different position. When the hologram is viewed, each eye sees an image recorded at a different time. Because the brain expects both eyes to see the scene at the same instant in time it misinterprets the position of the moving car. If the car is moving from left to right (in the same direction as the camera) it will appear to be behind its correct position. If it is moving from right to left it will appear to be closer to the viewer than it should. If the car is moving toward or away from you there is error in both its left to right position and its in and out position which changes with viewer location. The magnitude of these errors is highly dependent on the object's velocity. The perceived position error of an object moving at moderate velocity can easily be greater than the distance that it moves in the hologram. We have derived, using a simple geometric model, a set of formulas which predict the perceived position and perceived position error of moving objects in holographic stereograms. Using these formulas designers of animated holographic stereograms will be able to compensate for errors in the perceived locations of moving objects. This will enable them to place moving objects in the correct positions relative to other moving and stationary objects. For example, the designer will be able to design a hologram where a car travels along a street without driving up on the sidewalk.
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