360-Degree Holographic Display

Researchers from the University of Southern California (USC) Institute for Creative Technologies developed a 360-degree holographic display, that projects three-dimensional images that can be seen from any angle at a reasonable distance. The researchers used a set of rendering techniques for their autostereoscopic light field display. The display system consists of a high-speed video projector, a spinning mirror covered by a holographic diffuser, and a specialized processor to decode uniquely rendered video signals transmitted from the computer.
3D object shown on the display is photographed by two stereo cameras (Credit: University of Southern California)
3D object shown on the display is
photographed by two stereo cameras
(Credit: University of Southern California)

The holographic display system uses a standard programmable graphics’ card to render over 5,000 images of interactive 3D graphics per second, projecting images to 360°-degrees with 1.25° degree separation and up to 20 updates per second. The images are projected onto a spinning anisotropic reflector and a motion-tracked vertical parallax is used to support 3D movements with perspective-correct geometric cues. The USC team demonstrated this technique with interactive raster graphics using a tracking system to measure the viewer’s height and distance from the projected images. 

According to the scientists, their device incorporates several technical innovations including the development of new techniques for acquiring and rendering interactive 3D OpenGL graphics and photographed light fields. In this project, the scientists concentrated on the advanced mathematical calculations needed in order to generate 3D images at a correct perspective for viewers of different heights and at different distances from the display. The team said that one of the main challenges they had faced was achieving real-time updates using the projector at very high frame rates (many images projected per second) while still using standard DVI graphics’ hardware.   

The researchers say that they expect this approach to be viable at the consumer level in just a few years time. “Our hope is that our contributions will enable other researchers in computer graphics and immersive displays to develop new 3D technology and content. 3D displays such as ours should become increasingly practical in the years to come as the core graphics and image projection components decrease in price and increase in capability”. 

A single photograph of the original object sitting to the right of its virtual version shown on the 3D display (Credit: University of Southern California)
A single photograph of the original object
sitting to the right of its virtual version
shown on the 3D display
(Credit: University of Southern California)

The scientists presented their 3D projection technique at the SIGGRAPH 2007 Emerging Technologies Exhibition that took place this last August in San Diego, California. At the exhibition, the USC holographic display system was awarded the prize for “Best Emerging Technology”. 

TFOT covered several advanced display technologies including the Perspecta Spatial 3-D System, IO2 Technology’s Heliodisplay Floating Display and more recently Sony’s XEL-1 OLED TV and electronic paper

You can watch a video demonstrating this technology at the USC official website, or catch it at the upcoming 10th International Conference on Virtual Reality in Laval, France in 2008.