But Microsoft's struggles are good news for 3M.
Not only has the St. Paul, Minn.–based company managed to get sequential autostereo working well, it's gotten it small enough to fit in the device I'm holding right now. 3M's senior technical manager, Bill Bryan, doesn't mince his words: "There hasn't been a bigger improvement to the viewing experience since the introduction of color screens." Of course, he would say that, wouldn't he? But there's no denying that 3M's new Vikuiti 3-D technology [PDF, 323 KB] is something special.
I viewed the Vikuiti 3-D effect on both 3-inch and 9-inch screens, and I found it to be startlingly bright, crisp, and vivid when seen head-on. If you do move to one side, the images fade gracefully into 2-D. At a trade show last May in Seattle, 3M's LCD business director, Erik Jostes, showed off a 9-inch model. The company was running a show reel of animated gaming characters and also some smooth, full-resolution video.
Basically, this is the 3-D display we've been promised in science fiction films for the last 50 years. And an early version of it, which suffers from slightly more cross talk than the 3M models, is available today, in Fujifilm's W1 3-D digital camera.
To understand the 3M system, start with the fact that most LCD screens are transmissive; they have a backlight that shines through the liquid crystal panel to form an image. In handheld devices, the backlight LEDs are located at the display's edge to save space. A single row of LEDs constantly shines into a plastic light guide that, as its name suggests, directs and disperses light in the correct direction—up and out of the display. For years, 3M has been creating optical films that help move this light evenly from the sides into, across, and out of the liquid crystal panels, increasing their effective brightness. The company has now come up with the Vikuiti optical film, which can direct images to one eye or the other.
This autostereo 3-D system has a light guide with a column of LEDs mounted on either side of the screen; the columns flash alternately 120 times a second. Each burst of light travels through the light guide as usual, then up into the Vikuiti optical film. Inside the film are microscopic bumps—finely engineered features that act as tiny lenses. When light from the left-side LEDs shines on them, they direct light to the user's left eye, and when light shines on them from the right-side LEDs, the image is directed to the right eye. Flashes of left and right light are easy enough to produce, but for the screen to form an image, the LCD panel above the film must be perfectly synchronized with those flashes, showing only the left image when the left-side LEDs are on and the right image for the right-side LEDs.
The Vikuiti screen has just one 3-D sweet spot, straight out from the screen. At this point it's definitely intended for personal viewing, not Super Bowl parties.
In order to direct light reliably to each eye at the correct viewing position, 3M needs to manufacture the microscopic lenses—the bumps—with extreme precision. The film is just 150 micrometers thick (around twice as wide as a human hair), with the lenses measuring a mere 50 to 70 µm. Perfecting this film took 3M over three years, and developing the techniques necessary to produce the film in commercial quantities took another year.
With no optical barriers or screen-mounted lenses to reduce the brightness or resolution, the 3M film creates autostereo 3-D video that looks just as sharp as traditional 2-D images. But 3M's Vikuiti film shares some of the problems of other 3-D systems. Like the Nintendo 3DS's parallax barrier system, the Vikuiti 3-D effect works in only one direction, typically landscape. Rotate the screen, as cellphone users are in the habit of doing, and the 3-D effect simply disappears. The 3-D effect is also sensitive to interpupillary distance.
Finally, the effect requires a high-speed (120-Hz) LCD panel to deliver those sequential frames without jerkiness. These are more expensive than standard 60-Hz LCD panels. "The panels have to catch up. The graphics chips have to catch up. And because you're driving the LCDs harder, the power consumption will be higher in 3-D mode, too," admits 3M's Jostes. "If you want 3-D, you essentially have to double the processing speed." In short, it needs the kind of high-powered smartphones and tablets that are only just starting to arrive in the marketplace. These are unlikely to add pricey 3-D features until manufacturers perceive a real consumer demand, although Chinese company Rockchip has demonstrated a prototype autostereo Android tablet.
"With the first panels, there will be a slight cost premium," says Bryan. "There has been a chicken-and-egg situation around 3-D—how can you make a device when there's no content? And why make content if there's no device to view it on?"
Today, however, the Nintendo 3DS and its high-profile games are hatching chickens and laying eggs simultaneously; the industry could finally be gearing up for a handheld 3-D revolution. Unlike 3-D movies that require expensive multicamera setups, 3-D games can be developed at a premium of just 10 to 15 percent over their 2-D equivalents, according to game analysts at Futuresource Consulting. "Now that Nintendo has come out and said we're going to do 3-D, other companies will think about moving towards it as well," says Jostes. "Our expectation is that demand for 3-D is going to be driven by gaming."
Steve Vrablik, a director of business development at Toshiba America Electronic Components, is thinking even bigger. His company supplies LCDs to smartphone manufacturers and showed the 3M Vikuiti film in several devices at a recent trade show. "Last year, people looked at the prototypes and walked away," he says. "This year, they're saying, let's talk."
Glasses-free (and headache-free) 3-D could be the new must-have upgrade for cellphones—like GPS location, digital photography, and music playing before it. Industry research association DisplaySearch predicts that by 2018, mobile devices will have leapfrogged televisions to become the most popular 3-D gadgets, selling over 70 million units a year. MIT's Bove won't predict which autostereo technology will triumph, but he is convinced that the most successful devices will all be handheld.
"There are lots of things you can do on a screen the size of a business card that you just can't afford to do for a larger display," he says. "Whatever your magic component is in this domain, you don't need a lot of it."
And without those headache-inducing spectacles to contend with, you shouldn't need a lot of Tylenol, either.
About the Author
Mark Harris is a British technology and lifestyle reporter based in Seattle. Although wowed by 3-D View-Masters as a child, he credits the 1953 classic House of Wax, starring Vincent Price, for triggering a lifelong fear of 3-D glasses (and of Madame Tussauds). It took interacting with the latest glasses-free gadgets to finally cure his phobia. He writes regularly for The Sunday Times, The Economist, and Wired UK.