James Brown's Latest 3D Displays Are Entirely Solid-State — And Yes, They Play Doom
No more spinning LED matrices of death, these displays are inert glass blocks etched with internal point-clouds for external illumination.
Maker James Brown is back with another three-dimensional volumetric display, only this time there are no terrifying rapidly-spinning LED arrays in sight thanks to a new and considerably quieter solid-state approach.
"This [display] does away with the wildly spinning arrays of LEDs [of previous displays], instead using projection mapping onto a point cloud etched inside a block of glass," Brown explains of his latest voxel-based 3D display. "It has a resolution of around 38000 points — not anyone's idea of HD, but enough for playable games (if you're generous with your definitions of 'playable' and 'games')."
The new solid-state displays build on Brown's earlier work on volumetric rendering, which previously relied on spinning LED matrices — and a "dizzy" Raspberry Pi as the display controller — at high speeds inside a protective glass sphere. The effect was impressive, using persistence of vision to create a floating 3D image viewable from any angle — but the noise and worry of things disintegrating and flinging themselves outwards at high speed were always present.
Brown's latest displays are a quieter and safer affair, being entirely solid-state: a point-cloud of volumetric pixels, of voxels, is generated then etched into a block of glass — in exactly the same way as the glass sculptures you see with floating dolphins and the like inside. The block is then positioned at a very precise point away from its light source, a small projector, which illuminates the voxels to create a colorful, animated, three-dimensional though admittedly somewhat low-resolution image viewable from any angle.
Unlike the fixed-image sculptures, the voxels can be illuminated to create dynamic images — which, as is typical for Brown's demos, is shown off with a game of Doom modified to use voxel models plus the classic Acorn Archimedes title Zarch. "The stack of optomechanical [alignment] stages was rescued from a local lab clearout some years ago," Brown notes. "The next step for this project would be to get rid of that, build a solid mount in a nice housing, and perform the alignment in software."
More details are available in the video above, while the source code is available on GitHub under the permissive MIT license. More information can be found in Brown's Mastodon thread.