Interactive 3D images that appear to float in the air, above a table that a group of people can stand around without needing any special headsets or glasses: that’s what South Australian company Voxon Photonics has built with its US$10,000 VX1 table. Such things have been a long time coming to the real world. VR and AR can both somewhat replicate the experience, but they require headsets. In the best case, these are a bit antisocial, stopping you from looking others in the eye. In the worst case, they completely remove the wearer from the real world to immerse them in virtual space. The VX1 table from Voxon Photonics, on the other hand, requires no headset or eyewear. It operates more or less exactly like the hologram table in Star Wars, albeit usually with a glass dome over the top of it, and can display an 18x18x8 centimeter holographic image, video, game or interactive data visualization.
The VX1 table can best be described as 3D printing its image in the air. It breaks a 3D form up into horizontal layer slices, then achieves the mind-bending trick of projecting these slices onto a single piece of rear projection glass that’s being flung back and forth in the air at 15 cycles per second on a set of harmonic resonance springs. The system tracks the location of the glass and synchronizes it perfectly with a 4,000 frames per second projector, so that each slice is projected at exactly the right height. The slices are stacked and re-stacked so fast that your eyes can’t track the motion, and an object appears to float in the air. Since it’s being re-drawn both on the up and down swing of the glass, you get a hologram video refresh rate of 30 frames per second, and the illusion is terrific.
Voxon’s glass shaker might not scale up well – bigger versions are much harder to shake back and forth at a rate that gives you a satisfying video frame rate – but the company has another trick or two up its sleeve. Using a rotating screen that looks something like a drill bit, with ramps and drop-offs, it’s possible to make a much larger volumetric display that relies on projectors coming down from above.