Why do we need special glasses to see 3d movies?

Question by brianmatthewkessler: Why do we need special glasses to see 3d movies?
When I was a kid, I remember going to a hologram museum in NYC. The holograms were so realistic that as a kid, I tried to reach out and touch several, earning the ire of the security guard who was afraid I would forever ruin them with the oils on my grubby little finders. No glasses were needed for these, and they were so much more convincing then anything I’ve ever seen in a cinema.

Is it impossible or just cost prohibitive to make entire movies using a similar technology?

Best answer:

Answer by Mickey Mouse Spears
It’s not so much cost prohibitive or impossible; it’s just that the technology you’re talking about has a very narrow viewing angle. New technologies are emerging that will allow for 3D viewing without the use of glasses. Nintendo’s new handheld system 3DS will use it. I believe it’s called autostereoscopy.

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