There’s a type of dust-collector that’s been popular since the 1990s, where a cube of acrylic or glass is laser-etched in a three-dimensional pattern. Some people call them bubblegrams. While it could be argued that bubblegrams are a sort of 3D display, they’re more like a photograph than a TV. [Ancient] had the brainwave that since these objects work by scattering light, he could use them as a proper 3D video display by controlling the light scattered from an appropriately-designed bubblegram.

Appropriately designed, in this case, means a point cloud, which is not exactly exciting to look at on its own. It’s when [Ancient] adds the colour laser scanning projector that things get exciting. Well, after some very careful alignment. We imagine if this was to go on to become more than a demonstrator some sort of machine-vision auto-aligning would be desirable, but [Ancient] is able to conquer three-dimensional keystoning manually for this demonstration. Considering he is, in effect, projection-mapping onto the tiny bubbles in the crystal, that’s impressive work. Check out the video embedded below.

With only around 38,000 points, the resolution isn’t exactly high-def, but it is enough for a very impressive proof-of-concept. It’s also not nearly as creepy as the Selectric-inspired mouth-ball that was the last [Ancient] project we featured. It’s also a lot less likely to take your fingers off than the POV-based volumetric display [Ancient] was playing DOOM on a while back.

For the record, this one runs the same DOOM port, too– it’s using the same basic code as [Ancient]’s other displays, which you can find on GitHub under an MIT license.

Thanks to [Hari Wiguna] for the tip.