[doc_holliday]

Awesome, I am thinking this could be used to create an animated hologram by quickly changing the polarization of the indcident light on the hologram.

That would be very impressive to see.

[dTal]

You can already do that quite well by recording two different holograms on the same plate with different reference beam incident angles. You select the image by varying the angle of the replay light. You can fit at least 4 images on a plate that way (left, right, up down).

This technology is very cool, but sadly like many holographic research projects it's a) impractical and b) not in demand.