Articles and whitepapers

OLED, 3D TV, SHV - TV Technologies of the Future (1/10/2008)

By Yasmin Hashmi, HiddenWires

Just as the market is getting used to the idea of high-definition TV, we are reminded that technology never stays still. At recent broadcast equipment trade shows, we've been treated to a glimpse of what eventually lies in store for the consumer. System integrators need not worry - mass market products based on OLED, 3D TV and Super Hi-Vision technology are some way off yet, but forewarned is forearmed, especially when wiring for the future.

OLED

OLED (Organic Light Emitting Diode) displays promise more contrast, no imaging blurring, lower power consumption and thinner displays.

Instead of conventional LCD technology, OLED is self-luminous, that is, a layer comprising thin films of organic compounds emits light when a current passes through it - a synthetic version of the electrophosphorescence that occurs naturally in fireflies and many sea creatures. OLED displays therefore require no back- or side-light and no filters, and offers true blacks, since when a pixel is off, it is truly black. And since no backlight is required, less power is consumed, and the display can be very thin. The Sony XEL-1 OLED TV for example, that made its European debut at the IFA show, is just 3mm thick.

The Sony XEL-1 OLED TV is just 3mm thick.

Currently OLED displays are relatively small. The Sony XEL-1 for example, is just 11", although a 27" prototype was also shown by Sony at CES 2008. In addition, Samsung showed a 31" prototype OLED TV this year, and many of the major manufacturers are promising larger screen sizes within the next few years.

3D TV

3D or stereoscopic cinema experiences using special polarising glasses, have been around for some time. The latest productions, are causing quite a stir - the remake of 'Journey to the Centre of the Earth' for example, to which we were treated courtesy of Texas Instruments at the CEDIA US Expo in Denver, is apparently earning more from its 3D version than its standard version. We were given sturdy black plastic spectacles to wear, and dutifully flinched to avoid objects that seemingly lunged at us.

Frame from Journey to the Centre of the Earth, Copyright Warner Bros. Pictures.

With the equipment required to make such films now more sophisticated than ever, we are apparently entering the 'Year of 3D', and so we can expect the number of 3D productions to grow significantly. Indeed 3D is no longer reserved for cinema or for post-produced content. In March this year, the BBC delivered the first live test screening of an international sports event via satellite in 3D HDTV, and at the recent IBC (International Broadcasting Convention) show in Amsterdam, the first transatlantic high-definition 3D telecast was made between Los Angeles and Amsterdam.

3D TV works on the principle that each eye views a scene from a different angle, which is combined in the brain and used to judge depth.

Left and right eyes see slightly different images which are combined by the brain to judge the depth.

3D displays therefore, must get a distinct image into each eye of the viewer. With the new Samsung 3D-ready plasma TVs, an external PC is required that synchronises left- and right-eye images with special shutter goggles via IR, so that the right eye does not see the left image, and so on.

An alternative autostereoscopic display (that does not require glasses) is the Philips 3D LCD TV. This employs multiview lenticular lens technology to project slightly different images to viewers' left and right eyes, while allowing them to change position in front of the screen without losing the 3D effect.

The Philips 3D LCD TV.

The effect of the Philips multiview lenticular lens, showing the difference between what is projected to one eye and the other.

In general, there are limitations to 3D technology. It is not portable across all display sizes, the distance of the viewer from the display matters, as does the resolution of the display, and the distance between a person's eyes. So while it is intended to make 3D TV ubiquitous in the next five years, obviously a lot of development work is required before it becomes the same experience for each person.

Super Hi-Vision (SHV)

We first saw Super Hi-Vision (a.k.a. Ultra-High-Definition) TV demonstrated at the NAB (National Association of Broadcasters) convention in Las Vegas in 2006. It was stunning - it was on a large projection screen, and in one of the demonstrations the camera panned around a sports arena and you could distinguish the individual faces of people in the crowd.

Data size comparison between HDTV, 4k and SHV.

Developed by the Japanese national broadcaster NHK, Super Hi-Vision uses a 7680 x 4320 pixel system - 16 times the pixel resolution offered by the highest-quality 1920 x 1080 pixel HDTV currently available. The sound is a 22.2 system, i.e. there are three layers of loudspeakers and two sub-bass channels.

The 22.2 multichannel sound system used for Super Hi-Vision. The upper layer (blue) comprises 9 channels that provide an immersive sound field and special effects, and widen the optimum listening area. The middle layer (orange) comprises 10 channels that provide a basic sound field to envelope the listener. The lower layer (green) comprises 3 channels that provide an elevated sound field coincident with cues across the screen. There are also 2 low frequency effect channels (yellow).

At the International Broadcasting Convention in Amsterdam, thanks to cooperation between the BBC, NHK and Italian state broadcaster RAI, we were treated to the first demonstration of Super Hi-Vision being transmitted live. Hosted by Maggie Philbin (former presenter of the BBC's 'Tomorrow's World' TV programme), the event saw images being transmitted live from the top of London's City Hall using MPEG-2 compression over an IP infrastructure provided by Siemens IT Solutions via a Cable & Wireless Gigabit Ethernet fibre connection. There were also recorded feeds from a server in Turin using MPEG-4 compression over satellite. Both feeds were in turn displayed using an 8k x 4k projector, as well down-converted to two 3840 x 2160 pixel LCD displays using the Dirac algorithm. Developed by the BBC, Dirac uses wavelets - a radically different technology to AVC.H.264 and MPEG-2 and which is very efficient at coding high-resolution images. Dirac solves the problems that traditional wavelet compression had in achieving smooth motion performance, and is now awaiting adoption as a standard.

Example of a Super Hi-Vision demonstration theatre.

While the London pictures reproduced amazing detail of the scenes surrounding City Hall, such as traffic passing over Tower Bridge and a pigeon flying past the Tower of London, it was the surrounding sound that was remarkable. With 17 microphones in position to give true 3D sound, you could hear detail of the traffic, construction work, scaffolders, trains going past, and river boats, none of which interfered with the commentary of the presenter.

The NHK suggests that it will take at least ten years to make broadcasting of SHV to the home a reality, but in the meantime, more public demonstrations are expected to happen, with the BBC for example, planning to provide broadcasts in public areas for the London 2012 Olympics.

Conclusion

These new TV technologies promise to add exciting new dimensions to the audience experience of TV and gaming in the home, but before you convince your clients of their virtues, remember that HD was first demonstrated around 20 years ago, and is only now being widely adopted. Still, technology has moved on since then, and things tend to develop at an increasing rate, meaning that marketable models of OLED TVs might be available next year, with 3D and SHV TVs five and ten years away respectively.

On a practical note, the minimum screen size in the home to be able to discern the difference between HDTV and SHV is estimated to be 72-100". So while the NHK is developing such screen sizes, they might also think about a 'knock-through' specialist arm to help with removing the occasional internal wall.

Yasmin Hashmi is the Editor of HiddenWires magazine.