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adastra22 • today at 4:40 AM • 2 replies • view on HN

Very few people in the comments seem to understand what holography is. A hologram is not a “3D display” that mimics a sci-fi movie or TV show. A hologram is photographic media / display technology that records and transmits phase as well as intensity of incident photons. By capturing all the properties of the electromagnetic field that strikes the film, and re-emitting the same EM wave when stimulated, the hologram ends up being a full “3D picture” because after all, the light that hits your eyes ends up being the same as if you were looking at the actual scene. But that’s a consequence, not the defining property.

3blue1brown has a great explainer video on what holograms are: https://youtu.be/EmKQsSDlaa4


Replies

margalabargala • today at 5:32 AM

I don't understand the distinction. You said it's not a 3d display, then described a 3d display technology.

That's like saying a CRT doesn't display a picture because it energizes pixels only one at a time.

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SwtCyber • today at 5:27 AM

The irony is that actual holography is arguably more impressive than the sci-fi version once you understand what's happening