July 12, 2012

MIT Team Edges Closer To Glasses-Free 3D

Michael Harper for - Your Universe Online

Hollywood has already taken full advantage of our fascination with all things 3D, releasing thrillers, animated films, and even 20-year old movies with the use of that far-out, three-dimensional technology. There´s even been a push to bring this tech into our living rooms and pockets with 3D televisions, 3D smartphones and 3D gaming platforms.

While our appetite for 3D may be insatiable, the technology is still less than perfect. The most common complaint about this “realistic-ish” media is right in front of our faces“¦and on our noses: Those awkward glasses. Glasses-free 3D is making its way to the market, albeit very slowly. Toshiba, for instance, has a glasses-free 3D TV available. The 55ZL2 also displays a super-high-definition 4K picture, and costs around $11,000.

The researchers and scientists at MIT have been working on their own version of glasses-free, however, and today have given a sneak-peak into how our movies and television sets could come to life, all without having to don those blue-and-red spectacles.

Looking to combine the varying points-of-view inherent with holograms and the realism of 3D, MIT researchers have developed a working prototype with multiple LCD panels stacked together like a beautiful, electronics trifle.

Rather than rely on the complex hardware needed to create holograms, the MIT team uses these multiple LCD layers, called the Tensor Display, to produce the realistic 3D image. To really push these images over the top, the MIT team say they´d need to rely on an LCD with a refresh rate of 360 times per second, or 360 hertz. While this sounds intimidating, the team say such a panel may not be very far off, noting the market already has several 240-hertz LCD televisions. Only a few years ago, 120-hertz LCD TVs made their debut.

Holography works, it´s beautiful, nothing can touch its quality,” says Douglas Lanman, a post-doctoral student at the MIT Media Lab and a co-author of a resulting paper from their prototype.

“The problem, of course, is that holograms don´t move. To make them move, you need to create a hologram in real time, and to do that, you need “¦ little tiny pixels, smaller than anything we can build at large volume at low cost. So the question is, what do we have now? We have LCDs. They´re incredibly mature, and they´re cheap.”

Layered LCDs aren´t a new idea, however. For instance, the Nintendo 3DS–a glasses free gaming device–stacks two LCDs together to create the illusion of depth. The bottom screen quickly alternates between dark and light images while the top screen weaves these images together.

The Tensor Display, on the other hand, uses a single, unified backlit display, then filters the images through multiple layers of LCD panels, thus adding depth to the image, as well as a “moving” image to be viewed from different points of view.

Without these multiple LCD displays, the amount of information needed to generate such an image would be far too great. In order to create a realistic-looking 3D image, the LCDs would need a refresh rate of 1,000 hertz. The MIT team found that by simply adding more LCD panels, they were able to get the refresh rate down to 360 hertz. Each panel is able to display a different pattern, thereby sharing the load.

The team has written a paper about their new methods for achieving such realistic, glasses-free 3D, and will demonstrate a prototype at this year´s SIGGRAPH conference in Los Angeles.

“The paper reveals how you would greatly improve the realism, and image depth, and physical simplicity of 3-D display systems, particularly those that don´t require you to wear glasses,” says Gregg Favalora, co-chair of the SPIE Stereoscopic Displays and Applications Conference.

“It´s only possible when you have these really good mathematicians and signal-processing guys and optics experts all sitting in the same room.”