One Pair of 3-D Glasses to Bind Them All

If highways worked like 3-D TVs, you wouldn’t be able to drive Fords on GM roads and vice-versa. It sounds crazy, but that’s the state of affairs with 3-D active shutter glasses. The glasses that work with your Sony television, for instance, won’t work for watching Monday night football at a friend’s place on his […]

If highways worked like 3-D TVs, you wouldn't be able to drive Fords on GM roads and vice-versa.

It sounds crazy, but that's the state of affairs with 3-D active shutter glasses. The glasses that work with your Sony television, for instance, won't work for watching Monday night football at a friend's place on his Panasonic 3-D TV.

Blame the proprietary communication protocols that TV makers use to synchronize the glasses and TV sets. The result is that 3-D glasses are engineered so they will work only with the brand of TV with which they're shipped.

"There is a lot of confusion about 3-D glasses," says David Chechelashvili, who heads global retail and distribution at XpanD. "3-D TVs are an event-oriented social experience. You can't have that if everyone has different glasses that won't work together."

The good news is that the consumer electronics companies are finding a way to fix it. Companies such as XpanD and Monster are offering "universal" 3-D glasses -- a single pair of glasses that they promise will work with most 3-D TV set.

Meanwhile, the Consumer Electronics Association, an industry group, is finalizing standards for the emitters on 3-D TVs so all sets can use a common signal protocol. The hope is that it will lead to a standardization of the technology on the 3-D glasses and make the glasses interchangeable.

"Right now we hear from retailers and consumers that interoperability among glasses are a problem," says Brian Markwalter, vice-president of research and standards at CEA. "We need it to not get worse than it is."

Markwalter says CEA hopes to have the standards in place by November so consumers could see interchangeable 3-D glasses in stores by end of next year.

With movies like Avatar and Alice in Wonderland, Hollywood has helped 3-D technology make a comeback.

Though Nintendo and Fuji have announced 3-D gadgets that don't require glasses, the technology is effective only for small screens. The Nintendo 3DS has a 3.5-inch screen as does Fuji's newly introduced 3-D camera.

Larger 3-D displays still require viewers to wear special glasses. It goes to the heart of how 3-D displays work. 3-D screens flash two sets of images, one for each eye. 3-D glasses separate the images for the left and right eye so our brain can combine the two and perceive depth.

3-D glasses are currently available as active shutter--where a battery-powered glass has shutters that open and close rapidly alternating between the two eyes. That movement is synchronized to transmit the wanted image and block out the unwanted one. There are also passive glasses where polarized filters help direct the images to each eye.

In North America, movie theaters use passive polarized glasses but, for consumers at home, companies such as Sony, Vizio, Samsung, LG, Sharp and Panasonic are betting on active shutter glasses. The problem lies in the synchronization between the glasses and the TV set, which each manufacturer handles through a different set of signals.

"It's like a language and everyone uses their own," says Chechelashvili.

Retailers are also complaining about the lack of compatibility among glasses. As more 3-D TVs arrive on store shelves, retailers will be forced to carry multiple lines of accessories, each exclusive to a product. Imagine stepping into a Best Buy and trying to find the right pair of 3-D glasses to watch the demo of a 3-D TV.

To solve these problems, companies such as XpanD and Monster have created their version of the Babel fish: a pair of universal 3-D glasses that promises to work with any 3-D TV set. These glasses sense the infra-red pulses emitted by the TVs and time the shutters on the glass to sync with that.

But it is a trick more than a complete solution. In addition to signal synchronization, there are also color incompatibilities: TV makers have specific color characteristics and the glasses that come with each 3-D set are tinted to be compatible.

For instance, Samsung’s and Mitsubishi’s 3D glasses have a greenish tint, while Panasonic and Sony skew amber in color, explains HD Guru.

It means universal glasses won't offer the same quality of image as the 3-D glass handed out by the TV maker.

That's why industry group CEA hopes to step in with a fix.

CEA would focus on emitter standards, the source of the signals in 3-D TVs, says Markwalter.

"In an ideal world, emitters would migrate to this common specification, which would make for simpler glasses," he says. "We would then let the legacy stuff phase out of the market."

See Also:

Photo: (ripkas/Flickr)