Skip to content
Vrtron

Labs / D-Tank

A true volumetric display. Real depth, no glasses.

D-Tank draws a real three-dimensional image in a real volume of space. Not a stereoscopic trick, not a flat projection pretending to float: light is emitted from actual points inside the display, and the viewer can walk a full circle around the image. Built and demonstrated as a hardware proof of concept.

The idea dates back to the late 1990s. A full set of application studies followed in 2009-2011, and a formal 20-month engineering project, led by Ingo Mesche and Ing. Michael Bonello under AV Technologies / Vrtron, designed, built and tested the working unit. The project conclusion was unambiguous: the concept works and can be expanded to more complex configurations.

The idea

Depth that is actually there

Every mainstream "3D" display fools the eye: stereoscopic screens, shutter glasses and headsets all present two flat images and let the brain construct the depth. A volumetric display does the opposite. The image occupies a genuine volume, so depth cues are physically real, multiple people can view it at once from different sides, and nobody wears anything.

The application that motivated the work most was medical. A volumetric image of a patient, floating beside the operating table, would free surgeons from shutter glasses and let an entire team study the same anatomy from different angles simultaneously, including remotely during robotic procedures. The use-case studies below explore that scenario alongside fourteen others.

How it works

Painting voxels with spinning light

D-Tank exploits persistence of vision. Branches of LEDs, stacked through the full height of a transparent cylinder, rotate at 3000 RPM. Software converts a 3D model into spatial maps that switch each LED on and off at exactly the right angle and instant, temporal and spatial synchronisation, so the sweeping branches leave a stable, solid-looking image hanging in the volume.

Because the LED branches fill the cylinder from bottom to top, the result is a true volume of addressable points, not a single spinning plane. Image data streams over WiFi to an embedded system that rotates with the display; slip rings carry power only, keeping the data path free of mechanical contact.

Prototype footage

The proof of concept, running

Original workshop footage of the working unit. Lab conditions, not a product video: this is what a proof of concept looks like the night it first runs.

A note on the flicker: it is a camera artifact. The phone's frame rate beats against the display's refresh, the same effect that makes filmed CRT screens and LED car lights strobe. To the naked eye the image was solid and stable.

Use-case studies

Fifteen places a real 3D image changes things

A series of illustrated application studies (2009-2011) explored where volumetric display moves beyond novelty: medicine, education, museums, navigation, entertainment and the home.

Engineering

Designed like a product, not a demo

The project ran a full product-design methodology: a complete product design specification, quality function deployment to rank requirements (durability scored highest), and DFX reviews covering safety, reliability, manufacturability, assembly, serviceability and disposal. The mechanical design is rated for detached-component containment at speed, and the service-life target was set at 30,000 hours of testing.

Ahead of its time

The market arrived later, and only halfway

Years after this prototype ran, persistence-of-vision "hologram fans" appeared in shop windows and trade-show booths worldwide, built on the same base principle. They draw a flat image on a single spinning plane: viewed straight on, the picture floats; step to the side and the illusion collapses.

D-Tank was never patented, and the fans validated the easy half of the idea. The hard half, stacking the rotating layers into a true addressable volume with real depth from every angle, is what this project proved, and it is still not a product on any shelf today.

The proof of concept is archived, and the experience feeds directly into Vrtron's spatial and holographic work, from the full-size interactive holographic show built for Warner Bros. to current volumetric rendering research.