4 ms·

Not to take away the brilliance of what is achieved but I think hologram is the wrong word. This is purely about caustics. Amplitude engineering rather than pha

Not to take away the brilliance of what is achieved but I think hologram is the wrong word. This is purely about caustics. Amplitude engineering rather than phase. The calculations are just assuming light as particle, not light as wave. A true hologram uses diffraction grating effects and the phase difference from light. There was a very nice explanation on three-blue-brown recently. https://www.youtube.com/watch?v=EmKQsSDlaa4 https://www.youtube.com/watch?v=EmKQsSDlaa4 I don't think there are any phase effects in the parent attached? Or are there?

gpderetta 2y ago
Depends if we consider holograms only the specific technique of using phases to encode the information or any general technique that can encode 3D information on a 2D surface. This solution relies on a physicals height map (in the author's word, a 2.5D surface), whether that counts as a 2D surface I don't know. (and yes, I also saw the great explanation from 3blue1brown).
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- CyberDildonics 2y ago
  any general technique that can encode 3D information on a 2D surface This isn't 3D information on a 2D surface. If anything it is 2D information on a 3D surface.
  - gpderetta 2y ago
    The video shows that it projects a 3D surface as if it was storing volumetric information.
    - CyberDildonics 2y ago
      It isn't projecting a 3D surface (I'm not sure that even makes sense in this context) and it isn't storing volumetric information. It is just using refraction to make brighter and darker areas in its shadow/caustics to make an image. The paper is 10 years old at this point and linked by this article. https://rgl.s3.eu-central-1.amazonaws.com/media/papers/Papas2011Goal.pdf https://rgl.s3.eu-central-1.amazonaws.com/media/papers/Papas... https://nishitalab.org/user/egaku/tog14/yue-continuous-caustics-lens.pdf https://nishitalab.org/user/egaku/tog14/yue-continuous-caust... I think once you read the papers you will realize that the only thing 3D is the surface of the lens and that is only so it can get curves and angles for the refraction.

gpderetta 2y ago

Depends if we consider holograms only the specific technique of using phases to encode the information or any general technique that can encode 3D information on a 2D surface. This solution relies on a physicals height map (in the author's word, a 2.5D surface), whether that counts as a 2D surface I don't know. (and yes, I also saw the great explanation from 3blue1brown).

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CyberDildonics 2y ago
any general technique that can encode 3D information on a 2D surface This isn't 3D information on a 2D surface. If anything it is 2D information on a 3D surface.
- gpderetta 2y ago
  The video shows that it projects a 3D surface as if it was storing volumetric information.
  - CyberDildonics 2y ago
    It isn't projecting a 3D surface (I'm not sure that even makes sense in this context) and it isn't storing volumetric information. It is just using refraction to make brighter and darker areas in its shadow/caustics to make an image. The paper is 10 years old at this point and linked by this article. https://rgl.s3.eu-central-1.amazonaws.com/media/papers/Papas2011Goal.pdf https://rgl.s3.eu-central-1.amazonaws.com/media/papers/Papas... https://nishitalab.org/user/egaku/tog14/yue-continuous-caustics-lens.pdf https://nishitalab.org/user/egaku/tog14/yue-continuous-caust... I think once you read the papers you will realize that the only thing 3D is the surface of the lens and that is only so it can get curves and angles for the refraction.