James Brown's High-Speed Rotary Volumetric Display Experiments Take on New Depth — Literally
Plexiglass housings now make the displays slightly less terrifying to be around, even as the resolution has been majorly boosted.
Maker James Brown is still experimenting with turning rapidly-spinning two-dimensional LED matrices into depth-capable volumetric displays — with the latest incarnation offering a dramatically improved resolution and more convincing depth effect.
We last looked at Brown's somewhat-terrifying spinning 3D persistence-of-vision displays back in October last year, when the resolution was considerably lower than it is now. What was, then, a blocky image with a relatively shallow depth effect is now considerably more detailed — to the point of, in the latest demonstration videos, being able to easily identify voxel models based on designs from Id Software's original Doom.
Perhaps the biggest, change, though is the introduction of a new enclosure — sealing the rapidly-spinning LED matrices away from incautious and soon-to-be-removed fingers. Looking for all the world like a crystal ball, the spherical housing features a smoked plexiglass globe on a custom-built stand under which the driving electronics are housed.
"I've implemented parts of a content pipeline for rendering a scene on the PC and streaming it to this display, but writing video streaming code is so much less fun than playing with voxels that it may take a while to finish," Brown writes of the project's software side. "Here, I've stored the animation uncompressed on the display itself, and am updating it as fast as the [Raspberry] Pi's SD card can handle. (Not very fast.)"
"My target for this display is 600 rpm [revolutions per minute] — lower than that and it's too flickery; higher than that and I can't refresh fast enough to get 400 voxels around the circumference without dropping to 1 bpc [bit per color]," Brown adds.
Brown's latest demo videos are available in his Mastodon thread; "guess I'm doing a cone next," he writes of the next step in the project, which has already seen the creation of cylindrical and spherical displays.