How are holograms possible? | Optics puzzles 5

3d scenes on 2d film, and a diffraction lesson along the way.
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Slight correction: In the end, I referenced treating |R^2| as "some real number", so that it's only scaling O. This only makes sense to do because the amplitude of R is constant, or at least it varies only very slowly around a point. In this way, what I say a few moments later about making no assumptions about R is not quite right, we do assume it's a wave with relatively constant magnitude across the film.

Gabor's Nobel Prize lecture:
https://www.nobelprize.org/uploads/2018/06/gabor-lecture.pdf

A few resources we found helpful for this video
Seeing the Light, by Falk, Brill, and Stork
https://amzn.to/3Ngdiqh

Practical Holography, by Saxby and Zarcharovas
https://amzn.to/3ZR2MNN

Principles of Holography by Howard Smith
https://amzn.to/3ZOihFZ

Timestamps
0:00 - What is a Hologram?
3:28 - The recording process
11:45 - The simplest hologram
17:12 - Diffraction gratings
25:15 - Reconstructing the simplest hologram
28:24 - Conjugate image
31:11 - More complex scenes
35:58 - The bigger picture of holography
38:27 - The formal explanation
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https://github.com/ManimCommunity/manim/

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https://www.vincentrubinetti.com
https://vincerubinetti.bandcamp.com/album/the-music-of-3blue1brown
https://open.spotify.com/album/1dVyjwS8FBqXhRunaG5W5u

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