Existing ‘Passive’ 3D TVs Likely Won’t Cope With Blu-ray 3D, Experts Say

The sets, from Hyundai, JVC and, surprisingly, Toshiba, interlace the left- and right-eye images, and use a fine mesh of screen filters to oppositely polarize alternate picture lines. The viewer wears glasses with oppositely polarized lenses over each eye, so the left eye sees a left image built from odd-numbered lines and the right eye sees even lines.

The disadvantage is a half-resolution HD picture, while the advantage is cheap spectacles and easy broadcast of 3D video. The left and right images are transmitted, usually side by side, in a single frame and interlaced by the TV. Hence the U.K.’s BSkyB’s use of this system for its satellite 3D telecasts. The U.K.’s Virgin also uses it for its 3D cable demos. JVC has said it likes passive, polarizing displays because they let existing Blu-ray players, game consoles and set-top receivers deliver 3D, whereas Full HD active-shuttering 3D needs new players and receivers, or Sony’s promised firmware upgrade for PS3 (CED Feb 1 p4).

The Blu-ray 3D standard works quite differently. Two images in resolution up to Full HD 1080p are recorded on a disc that plays in a new Blu-ray player. These left and right images are alternately displayed at twice the normal picture speed while the viewer watches through battery-powered electronic shutter glasses. The glasses rapidly blank the left and right eyes. So, the viewer gets HD for each eye. Besides a new player, a new TV -- LCD, plasma or DLP -- is needed to display HD at twice the normal speed.

In the U.K., JVC’s Professional division offers its 46-inch GD-463D10 Pro 3D LCD display for about 7,700 pounds, including tax ($12,000). The company has sold “a healthy number to post-production companies … as through the drive of Sky they are working in a side-by-side format,” said Kris Hill, a sales executive with the company. Two of the JVC 3D sets were also by Glendale, Calif., post-production company Modern VideoFilm when working on director James Cameron’s Avatar, JVC Professional in the U.S. said.

"The GD-463D10 display does not support active shutter glass technology, the technology required for full resolution, per eye, 3D viewing,” Hill told us. Asked if JVC plans to offer displays compatible with Blu-ray 3D, he said “There are plans afoot to look at a multi-use professional monitor, however at this point no decision has been made and therefore there is no product time-line or estimation of price.” Other JVC executives have said the company’s promotion of passive 3D doesn’t mean it’s committed to the system in the long term.

Although new Blu-ray 3D discs will be capable of delivering 2D HD-video through existing Blu-ray players, and old 2D Blu-ray discs will play in 2D-HD on new Blu-ray 3D players, it seems unlikely that passive-polarizing TVs that deliver half-resolution HD to each eye will work with Blu-ray 3D players that deliver Full HD to each eye.

For 3D TVs and Blu-ray 3D players, the new HDMI Version 1.4 connection is required. The standard is administered by the HDMI Licensing Organization, which distanced itself from the half-resolution passive 3D approach. “JVC and Hyundai are using non-HDMI 3D, so we don’t have information on their technology,” the licensor told us.

Although Hollywood studios we queried were silent on the compatibility of Blu-ray 3D discs with passive-polarizing TVs, the Blu-ray Disc Association shed some light. “The Blu-ray 3D format does not attempt to support all the possible variations of split-resolution 3D, as there are many different approaches,” said Andy Parsons, Pioneer Electronics engineer and spokesman for the BDA’s North American Promotion Group. “The BDA specifies left- and right-eye channels from a compliant player, with each containing up to 1080p Full-HD resolution video,” he said. “I think a good way to support existing 3D TVs is to use an approach like Mitsubishi’s, which is to convert a Blu-ray 3D player’s output to a signal that the existing TV can reproduce. So if a display uses a side-by-side system, a dedicated box can convert the player’s 3D output into this type of signal."

We asked Parsons if Blu-ray 3D discs also would carry “passive” 3D versions of the content, that could be output by legacy 2D Blu-ray players for display on existing passive 3D TVs. That seems unlikely, he told us. “The approach BDA used was to devise a single method to master 3D content on the disc, to ensure that a Blu-ray 3D disc will play on a Blu-ray 3D player,” Parsons said. “If other approaches to 3D are used that don’t comply with the frame-by-frame Blu-ray 3D specs, it amounts to a proprietary encoding scheme that won’t work everywhere. So, I don’t think it’s likely that we'll see many passive or split-resolution 3D titles on the market, due to the uncertainty of how they would work with different legacy 3D TVs."

Separately, Parsons said that while Blu-ray 3D specs support Full-HD 1080p per eye, it’s not mandatory. “You can also put out 720p per eye,” he said. That’s up to the content owner. “As with 2D Blu-ray, it seems likely that the vast majority of content will be 1080p per eye for 24-fps film-based material,” Parsons told us. And, in yet another clarification of Blu-ray 3D standard, the BDA’s specs “don’t require 2D playback of 3D material on legacy 2D players if the 3D discs aren’t authored to work this way,” Parsons told us. “The reason? I'm told that some 3D content may not be able to support a 2D version of the film in the left-eye portion of the data stream, due to the way it was originally produced for 3D,” he said. “From what I can tell, this will be more the exception than the rule. But it would be inaccurate to say that 100 percent of Blu-ray 3D movies will be playable in 2D on existing 2D players."

Also separately, Toshiba baffled reporters by showing a passive 3D system at a London news conference this week. The demonstration comprised a Toshiba-branded passive-polarized 3D TV displaying computer-generated images viewed through passive spectacles from 3D-developer RealD. Previously, Toshiba seemed committed to the BDA’s standard. At CES, it announced plans to deliver several 3D TVs that use the company’s Cell processor (CED Jan 7 p3).

Equally baffling was the response of a Toshiba Europe executive to our reminder about the company’s commitment to using the Cell processor for 3D. “We are not saying that polarization is bad, but there is a better system,” said Olivier Van Wynendaele, assistant general manager for marketing at Toshiba Information Europe.

He later demonstrated Toshiba’s Cell TV and said, “The Cell processor can be used to convert 2D material to 3D. We will introduce a 3D TV in Europe and the U.S. during the second half of this year, and show it at IFA. I can only say it will not be a polarizing set. We want to use the best technology possible.” Pushed by our reminder that this appeared to leave only the active shutter option, van Wynendaele would only repeat that Toshiba would not be selling the polarizing system.