How 3D holograms work

The video explains holograms, which are flat 2D films that appear 3D due to motion parallax. Unlike photographs, holograms show different images based on the viewer's position. The creation of holograms involves splitting a laser beam into object and reference beams, which create interference patterns encoding 3D information. Holograms can reproduce the original object beam, making them indistinguishable from the real object. Additionally, each part of a hologram contains the entire image, unlike photographs. The video also clarifies that the Tupac hologram was a stage trick called Pepper's ghost.

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