6D Display at SIGGraph

Going to SIGGraph this week? That’s the Special Interest Group, Graphics expo that is part of ACM (Association for Computing Machinery) featuring all the latest in graphics related devices, including displays. And in case you missed it, the MIT boys (and girls) have come up with a new 6-D "passive reflectance field display" technology that is "light aware" dynamically changing with illumination.

Here’s how David Chandler of MIT News office puts it: "By producing "6-D" images, an MIT professor and colleagues are creating unusually realistic pictures that not only have a full three-dimensional appearance, but also respond to their environment, producing natural shadows and highlights depending on the direction and intensity of the illumination around them."

To illustrate the concept, MIT has posted a video called Towards Passive 6D Reflectance Field Displays. One sequence shows the display, which is composed entirely of passive optical elements, glued to an ordinary office window. The time-lapsed video shows the sun moving across the background of the display, and as it does this, the image of the vase evolves, with shadows changing with the movement of the sun as if it were a real vase.


Click to watch the video

The display concept is based upon integral imaging — a method that uses a 2D array of tiny lenslets to capture and image in multiple views. Unlike lenticular 3D display that can create multiple views in only one direction, integral imaging can create multiple views horizontally and vertically. As the viewer moves around the display (or the light sources moves in back of it), different views can be created.

To get to 6-D they add the element of light. As Chandler puts it, "The new ‘lighting aware’ system adds additional layers of lenses and screens to add two more dimensions of change. The image that is seen is then not only based on the position of the viewer, but also on the direction of the illumination.

Illumination effects are important as they introduce a degree of realism to the image. Associate professor at the MIT Media Lab Ramesh Raskar puts it this way, "the display should respond not just to a change in viewpoint, but to changes in the surrounding light." He gives the example of a hologram of a flower vs. the real thing... "Even if you have the best hologram out there, [it] doesn’t look real, [because] all the shadows and all the reflections on that flower are not mimicked on that hologram."

The group sees digital signage and entertainment as target area of application. At present, the handmade system cost about $30 / pixel. The research group developing the technology, consists of MIT Media Lab, and MPI Informatik personnel, and is partly funded by MERL (short for Mitsubishi Electric Research Labs). As we said, a prototype (low resolution) is being shown at SIGGraph this week, but they estimate the full technology is about 10 years off.

Got a minute, try brainstorming applications for this technology. How about an indoor shopping mall sign hanging under a sky light that gives different ads for upstairs and down stairs viewers and changes messaging depending on the time of day (breakfast, lunch and dinner ads–one for the upstairs McDonalds, the other for the downstairs Burger King).

OK, one more... an outdoor display at Disneyland, that gives messages in different languages depending on your horizontal position to the sign. In the vertical, kids get one message–grown ups another.

Go ahead, you can do much better than that...

By Steve Sechrist, DisplayDaily