Every time a research group releases a report about the state of 3DTV, we hear that consumers' primary complaint about current 3DTVs is the need to wear glasses. A number of manufacturers are working on glasses-free 3DTV (also known as autostereoscopic 3DTV); at CES 2012, I saw glasses-free demos from Toshiba, Sony, and Stream TV (Toshiba has said that it will introduce its glasses-free TV to the U.S. market this year). Unfortunately, none of these demos was especially impressive. In its current form, glasses-free 3DTV produces an image that lacks depth and detail and has a limited number of viewing positions. The latest company to tackle the glasses-free 3D challenge is Dolby, which has worked on the cinema side of 3D technology for years. Back at NAB in April, the company unveiled Dolby 3D, a suite of technologies (developed in partnership with Royal Philips Electronics) designed to offer full HD 3D content to all 3D-capable devices, including glasses-free 3D displays.
According to the original press release, the goal of Dolby 3D is to "improve the 3D viewing experience on displays of all sizes, including smartphones, tablets, PCs, and televisions. Dolby 3D is a complete system designed to work throughout the chain to deliver clear glasses-free 3D content that operates over existing distribution systems." Dolby 3D will provide tools to content creators, content distributors and display manufacturers to improve the 3D viewing experience at home and on mobile devices. You can get the full rundown on Dolby 3D on the company's website.
On the display end, Philips provides the glasses-free 3D panel. The most common method for delivering autostereoscopic 3D is by using a lenticular filter with many small lenses that direct the appropriate image to each eye to create the 3D effect (you can read more about this approach here). As with the current crop of passive 3DTVs, the lenticular approach embeds the left- and right-eye images together in the same frame, cutting the amount of resolution to each eye. To deliver a more detailed 3D image, you need to start with a more detailed (i.e., higher-resolution) display. At NAB, Dolby showed off the technology on a 56-inch 4K LCD panel, sending an approximately 2K image to each eye. From the reports I saw, attendees had a favorable response to the Dolby 3D demo, with Home Theater's Scott Wilkinson describing it as "the best autostereoscopic display I've ever seen." Toshiba's glasses-free 3DTV also uses a higher-resolution QuadHD panel. Clearly, one of the keys to bringing successful glasses-free 3DTV to market is to speed up the development and rollout of 4K displays.
The lenticular approach also requires you to view the image from a particular viewing position to get the 3D effect; this isn't a concern when viewing glasses-free 3D on a small-screen gaming console or a phone, but it's a major problem on a big-screen TV. Manufacturers are continually working to increase the number of viewing zones for larger-screen TVs and to minimize the noticeable transition from zone to zone. Dolby's NAB prototype had 28 zones (in comparison, Toshiba's glasses-free 3DTV demo at CES had nine zones).
In addition to improving the glasses-free approach, Dolby 3D is also designed to offer a better 3D experience on existing 3DTVs, particularly in 3D content delivered by cable/satellite providers. Because the broadcasters don't want to use additional bandwidth to deliver 3D content, they employ frame-packing technology to embed the left- and right-eye images in the same frame, in either a side-by-side or top-and-bottom format. This delivery method halves the image resolution. According to Thom Brekke on the Dolby Laboratories blog, "One of the many capabilities included in Dolby 3D is the ability to send a lightweight, full-resolution stream over existing networks. Think Blu-ray quality 3D from your cable or satellite provider. This aspect of the technology works with glasses-free Dolby 3D-equipped televisions, as well as existing sets that use glasses." Another stated benefit of Dolby 3D is the ability of the end user to easily tailor the 3D depth to according to preference and screen size, be it a 65-inch TV, 15-inch PC, or seven-inch tablet.
Because Dolby 3D is an end-to-end solution, the company needs to convince all of the parties along the 3D chain to get on board before we'll see tangible results. Dolby has certainly had success with end-to-end solutions on the audio side of the equation. It remains to be seen if they can help usher in a new era of glasses-free 3D that will truly excite consumers.