Multivox: Volumetric Display | Hacker News Reader

Multivox: Volumetric Display

github.com

327 pointsjk_tech45 comments

In case you miss it, a video of the thing in operation is linked: https://youtu.be/pcAEqbYwixU

Reminds me that there are limitations to volumetric displays—namely that, since you have no idea where the viewer is located, there is no backface culling you can perform. So it seems to work best for "cutaway" views.

I'd like to see one in person. Might be "magical" — the video only kind of hints at this.

I can see it making a great "radar" peripheral for 3d space games, think Elite Dangerous or No Mans Sky that both have one in their cockpits.

If only Halolens took off. Now we have to make do with Chinese drone performances at night.

I think this limitation could be overcome with the right hardware.

For example imagine a spinning display like those of the article but somehow tuned so that they are only visible when exactly head on. In that case, you know where the observer is: right in line with the screen. So you can have backface culling; as the display spins you render all 360 (or however many) viewpoints.

Now granted, this doesn't deal with how high or low the observer is. We'd need to find another solution for that.

> imagine a spinning display like those of the article but somehow tuned so that they are only visible when exactly head on

I don't understand: doesn't defeat the purpose of a volumetric display (seeing what is displayed from multiple point of view) ?

This would be a poor man's "lightfield" display: as you move left or right you see a different perspEctive, just like you would if it were a physical object on the table instead of the spinning screen contraption.

So you would indeed see different points of view.

that's just a flat display with extra steps

It’s different from a flat display in that if you walk around it, you see a different perspective. And it works with any number of viewers.

I think it's worth pointing out that "in operation" here means it's running Doom. Which I was not expected, and somewhat blown away (heh) by. Very very cool.

These displays use rotating mechanisms.

This ones does not: https://www.youtube.com/watch?v=wrfBjRp61iY

Volumetric display in the video above uses static projector whose pixels light up etchings inside solid glass.

The same person built both of these.

feel like I saw this in a hackaday, at least remember hearing the podcast about projecting all the rays at all intersections, it was green though maybe I'm thinking of something else

oh wow yeah I've seen a lot of this channel's work before the lego display, the CV fiber optic bundle display

Thank you for sharing - it's a brilliant piece of tech. I posted this earlier but it didn't catch on with upvoting

https://news.ycombinator.com/item?id=46137203

Whatever the outcome, when someone sets up an optical table, I'm sold.

Speaking of tables, you probably already know about Tilt-Five? If not, they made a very neat social AR system focused on tabletop gaming.

https://www.tiltfive.com/

This one uses a projector on oscillating rubber bands so that you can reach in and touch it: https://www.youtube.com/watch?v=4wwKOXxX9Ck

That’s actually really neat. It’ll be interesting to see how durable these kinds of displays end up being. Rubber bands tend to loosen up with use, or when exposed to uv rays.

I'm sure I'm not the only one who thought "why not vacuum", so I went and found the creator's reasoning [0] for why it's not a priority:

> [I]nside the dome the air quickly ends up rotating at the same rate as the rest of the mechanism. It's reaching its design speed with the motor at less than half duty cycle. Even if it were practical to make the whole thing airtight, it doesn't solve a problem that I currently have. The sound it makes doesn't come from inside the dome but from the motor in the base.

[0] https://www.youtube.com/watch?v=pcAEqbYwixU&lc=UgygtRUb6XZyu...

[Self-reply with side-topic] Assuming a rectangular display rotating in standard air... what glass enclosure would be best?

My intuition says "change the sphere to a cylinder", because then we can minimize how much air could be passing around the sides and top of the display-rectangle, potentially curling around and causing turbulence and noise.

However, that introduces a new issue of visibility: Big flat surfaces have different glare/reflection problems than a spheroid does. It may become harder for the user to see clearly, whether from external glare or from internal reflections in a dark room. What if the top face of the glass cylinder was very slightly curved outwards, to avoid the worst-case scenario where you just can't look down into the device from certain angles? Depending on the refractive index of the glass, it could just be a thicker top, so that it doesn't create dead-space on the inside.

Whoa, the intersection of different skills necessary is incredible.

- software

- math

- 3d printing

- electronics

Very impressive.

Before I watched the video, my brain ran ahead and I imagined it would be one of those led "fans", except also rotating around it's base. It might be harder to sync the two rotations, but you'd have much less mass in motion that way.

The solid state ones are cool! The real mystery there is how the pixel volume was manufactured -- it doesn't seem like something easily DIY'd

There are companies that laser-'etch' 3D images into glass. I guess it's not that hard to find one that accepts a list of xyz coordinates.

This looks crazy good! I love how you made it easy to see how balanced it is.

Shameless plug, I made a similar thing but for bike wheels!

https://youtu.be/o8n-bu2kKnc?si=BPn8tRbFTiQROJg1

This guy's entire output is incredible (from alien tellitubbies onwards). Go moose! https://mastodon.social/@ancientjames

My fav: a two-by-two LEGO block that can run and show Doom. https://www.hackster.io/news/james-brown-s-tiny-lego-brick-c...

An earlier iteration of the same block is imo more impressive in its creativity - https://www.youtube.com/watch?v=6wBrOV2FJM8&t=720 - such an unexpected and yet completely natural extension of the brick set.

I wonder if you could have a vibrating chladni plate with sand on it and you match when the sand should jump with the light that's meant to be at that spot. You get the interruption of light looking like a mid-air pixel and then when it isn't needed it drops back down allowing light to pass through. Kind of like one of those mist-screens except there isn't mist where you don't need it.

I once considered making a spinning persistence of vision similar to this one specifically for visualizing lidar data from a spinning automotive lidar. The lidar has 128 beams and you could make a spinning array of 128 1D LED displays at exactly the same beam angles to recreate the point cloud from the lidar.

Anyway, I was too lazy to make it, but it's super neat to see that someone actually made something similar.

Never knew this was possible. I hope some huge company with lots of resources jumps on this and drives up the resolution and price.

Why would they?

I mean, I think it's SUPER cool and would not mind one sitting on my desk.

But from a product standpoint...? It doesn't scale well in size, resolution or refresh rate.

VR is pretty much better if you want a the kind of immersion I think you'd be looking for, and even selling that is hard.

Looking Glass displays (not the "hololuminescent" ones) solve many of the same things (multiple viewers, no glasses) while looking good, and in principle you could build a cube out of them, although the display can't be seen from the full 180 degrees.

>drives up the resolution and price.

Uh, I get the former but why the latter?

meant down :p

Check out Voxon [1]. From the specs and youtube videos it seems like it's working on the same principle (rotating LED screen). Fun fact, it was co-founded by none other than Ken Silverman (the creator of Build engine) [2]. They've been pushing commercialization of this technology for years now.

[1] https://www.voxon.co/ [2] https://en.wikipedia.org/wiki/Ken_Silverman

My son works on this. It's pretty cool tech.

Also check out the company named "Light Field Displays" for stunning displays. Not exactly the same as volumetric. Arguably better in some ways. Definitely more expensive though.

https://www.holoxica.com/light-field-displays

interesting it is different than these kinds

https://www.youtube.com/watch?v=nM7wsXcYQFM

which I guess is the "volume" part

Amazing, finally a refreshing, motivation source!

Would be great having one of these hooked up to an LLM agent so it can be somehow “embodied”. Like a Siri + volumetric display + speaker. Waiting for a company to build this.

Like the Morpheus character near the end of Deus Ex.

Exactly, but more friendly

DOES IT RUN DOOM?! seriously

yes.

It was right there[1] in the assembly video.

[1]: https://youtu.be/pcAEqbYwixU?t=1038

Doom or Quake renderer coming when?

Reply on news.ycombinator.com