Remember if you want a multi-projector, edge blended, setup with active 3D, then all of the projectors would need to have near perfect frame-level synchronized such that the switching between the display of right and left images occur a the same time. Otherwise the active 3D glasses would not be able to correctly sync up and correctly separate the right from the left images. I don't recall seeing that capability built into the projectors. Also when I was at Infocomm last summer several manufacturers, including Panasonic, were demo'ing edge blended, multi-projector setups, but all were in 2D. I don't recall anyone talking about such a setup for 3D.
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