3-D: Coming soon to a TV near you?

Caren B. Les, caren.les@photonics.com

The development of 3-D television has become an area of intense interest to manufacturers, according to market analysis firm DisplaySearch in its Quarterly TV Design and Features Report. The company notes that the manufacturers are seeking to retain consumer interest in the sets, for which average selling prices are expected to fall for the first time since the beginning of the flat panel model transition.

The report indicates that LED backlighting and 240-Hz LCDs will enable development of new features in TVs, particularly 3-D. The company forecasts that the number of 3-D-ready TVs will reach 64 million in 2018, up from 0.2 million units in 2009. It predicts that 15.6 million 3-D-capable TVs will be shipped in 2013, up from an estimated 1.2 million shipments in 2010.

“The main reason for this positive projection is the convergence of 3-D content, in terms of movies, games and, soon, broadcast content, and in hardware, in terms of good-quality 3-D displays and Blu-ray Disc players,” said Paul Semenza, senior vice president of DisplaySearch. High-density optical Blu-ray Disc technology, designed to replace the standard DVD format, is a key platform for movie content, and movies are the leading area of development for 3-D, he said.

“Furthermore, the high bandwidth required for high-definition 3-D movies will limit distribution – or make it expensive – via cable and satellite. So Blu-ray is a key link in the chain of delivering 3-D content to 3-D TVs. Agreement on a standard should help speed implementation of 3-D as a regular feature in Blu-ray players,” Semenza said.

The Blu-ray Disc Association released a Blu-ray specification in December 2009 that will leverage the advantage of the Blu-ray Disc format to deliver high picture quality as well as uniformity and compatibility across the full range of Blu-ray 3-D products, both hardware and software. The technology, which uses a 405-nm blue-violet laser, enables almost 10 times more data storage than a DVD.

Semenza noted that any multiple of a 60-Hz – or 50 in Europe – frame rate, including 120 Hz, 240 or higher, enables higher video performance. Specific to LCDs, the higher frame rate enables some compensation for the relatively slow switching time of the liquid crystal material, he said.

He explained that, in large screen sizes, this slow response can cause artifacts such as image blur, in which a fast-moving object appears blurred or skips across the frame. For any type of flat panel display, the higher frame rate can be used to display multiple channels of video, which can be used in conjunction with switching glasses to produce 3-D video, or it could be used to show multiple video streams simultaneously on the same display.

“The benefits of LED backlighting include wider color gamut, faster switching time, thinner-depth sets and the ability to have ‘local dimming,’ which increases contrast ratio and decreases power consumption. LED has only an indirect impact on 3-D – the fast switching of LEDs helps to enable the high frame rates needed to produce full high-definition 3-D video,” Semenza said.

From Avatar to awareness

“Awareness – despite the success of the film Avatar – is an industry challenge,” Semenza said. He noted that consumer surveys by the Port Washington, N.Y.-based NPD Group Inc. market research firm (of which DisplaySearch is a part) indicate that there is relatively low awareness of 3-D technology. The surveys also showed that consumers are not willing to pay a high premium for 3-D capability and that they would like a large amount of the content they watch to be available in 3-D.

“Finally, there are questions about usage modes – how much will consumers want to see in 3-D – sitcoms? local news? – and are there any health concerns with prolonged 3-D viewing,” Semenza said.

Glasses-free 3-D

“The key issue at present is interoperability of the glasses from different set makers; it is not clear, for example, if glasses produced for a Samsung TV will work with a Sony, or vice versa. It is probably not a difficult issue; it just needs to be resolved,” he said.

Perhaps the ultimate implementation of 3-D TV is glasses-free, autostereoscopic display. To achieve this type of display without any degradation in resolution or brightness, optical or other component technology must be added or integrated into the display.

“In the long term, a mix of 3-D offerings, including movies, live sports and gaming, will be needed to make the 3-D feature in TVs desirable to consumers. Active – shutter – glasses are required now and will be for the next several years, until the high-quality autostereoscopic displays are developed. These active glasses are heavier and more expensive than the passive – polarizer – glasses being used in cinemas; passive glasses are enabled through the use of two projectors that run simultaneously, something that would not be feasible in the home,” Semenza said.