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Colossal Holograms

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Re: Colossal Holograms

#101

This reminds me of https://www.youtube.com/watch?v=Jd3-eiid-Uw (2007) Johnny Lee's demonstration using head tracking with infrared led's and a wii remote to implement the same thing. Obviously that limits the effect to the individual's head being tracked, but its amazing its been 12 years since that demo and we're still trying to commercialize the same affect.

That was a great video, and highly hackerific. "That would be a bit goofy" is an expression you don't hear very often these days.

Re: Colossal Holograms

#102
post #100
post #99

Earlier quoted context omitted.

From back when I researched it, accommodation mismatch is a huge problem for a small (but significant) proportion of the population in terms of nausea or headaches. It's less of a problem for movie-theaters because accomodation is at infinity for the screen itself, so as long as they don't have too much for too long that is much closer to the viewer than the screen, it doesn't cause any issues, but it seems like it w…

The 3D glasses problem doesn't really apply here. With 3D movie glasses, everything is blocked out except for the 3D images. Some people feel queezy when their proprioception and visual input don't match. It's a little like car sickness. With the screen, they do match, as only what's on the screen is 3D. In that sense, it is like looking at a box with something 3D in it, versus being submersed inside something 3D lik…

The issue I'm thinking of was still an issue even with early HOP lenticular displays (IIRC philips had a 7-view one in the 90s), and I seem to recall reading research that specifically identified accommodation/parallax mismatch rather than anything else, which is why large viewing distances do not have this problem.

Re: Colossal Holograms

#103
A 3D hologram doesn't get you 3D medical records magically.

And if you have them, I reckon a screen with a mouse is all you need to view them to technically know how to proceed.

Usual marketing scam, make the public think creating a 3D hologram device will somehow get them 3D things.

Re: Colossal Holograms

#104
post #48

Earlier quoted context omitted.

Are the Looking Glass display real holograms with light interference patterns ? Or are they emitting different pixels in different view angles ?

Aren't those two things essentially identical, at least as far as the resulting wavefront goes?

In a sense, if the resolution is high enough. One notable limitation of the angular-pixel approach is that the angular resolution of the pixel becomes diffraction-limited as the pixel size shrinks - the puts you between a rock and a hard place with the twin goals of "small enough pixels that you can't see them" and "enough viewing angles that you can't perceive the steps", even if you had a hypothetical umpteen-zillion gigapixel display. "True" holograms are coherent across their entire surface, so they don't have this limitation.

This isn't even close, though. Horizontal parallax only and only a few dozen angles (over a wide FOV!) puts it more in the territory of lenticulars than true lightfield displays. To be fair that is enough to achieve a 'wow factor', and a true lightfield display is a Hard Problem (that Fovi3d are trying to solve, if you're interested in the state of the art).

Re: Colossal Holograms

#105

Not a hologram in the sci-fi sense, but still very cool. From what I gather, this is the same tech used in a 3DS - scaled up to an impressive scale.

its not. lightfield techonology is a completely different beast from parallax stereoscopy.

It's the same thing in reverse. You can use a camera to capture a light field, and then a screen with a complementary lens to project out (roughly) the same light field.

In fact, given the principle of the reversibility of light, if you had a screen the same size and pixel density as your camera sensor you could use the exact same lens array to output a close approximation of the captured light field, without any post-processing of the captured pixels!

Re: Colossal Holograms

#106
post #62

Earlier quoted context omitted.

There are multiple transparent lcd (or maybe led - idk) screens layered on top of each other. A different image is rendered on each layer to appear 3D. A single 8k video stream is sent to the display. Each 8k image is subdivided into multiple smaller images, one for each layer. So the entire image is 8k, not 8k per layer. I know one of the cofounders, Alex, a bit. He’s a really earnest and excited person. He’s been w…

Is this essentially the technology the 3DS used, only scaled up? (I ask for clarification, not to diminish the achievement. If it is, and it works well, it's still a nice advancement. Nor am I saying it was invented for the 3DS.)

As I recall the 3DS used a lenticular lens: you see different images based on the angle to the display. Wikipedia has some more information: https://en.wikipedia.org/wiki/Lenticular_lens
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