3D TV – Three Dimensional Television

Three Dimensional Television is going to be the latest must have technology for the home, and its arrival has been heralded in a major 2010 Consumer Electronics Show (CES) in Las Vegas, USA.

It might be difficult to believe, but the first experiments in three dimensional television date back to the early 1970′s when a research group based in the United Kingdom started to look at the potential of using certain exotic materials to create a 3-D TV effect. Now, four decades later, consumer 3-D televisions are all the rage at the 2010 Consumer Electronics Show at Las Vegas.History of 3-D

3-D has been employed in various media for over 150 years. Initially it was used in photography where two photographs of an object taken from slightly different angles were combined in a stereographic viewer to create a 3-D effect. After still photography it was the turn of the movie industry and the first 3-D movies began to appear in the 1920s. These movies required the use of special glasses with red and cyan lenses.

How does 3-D Work?

There are a number of ways of creating a 3-D image, but they all aim to achieve the same thing; to produce slightly offset images in each eye so that the brain combines them into a single 3-D image in the same way that it achieved depth perception in the real world.

One way is to use glasses with one red lens and one cyan lens. These are used to view images that are made with offset coloured layers. Each lens filters out one of the layers, so each eye sees a different layer and the brain combines them into a single 3-D image.

Another way of achieving a similar effect is the use of polarising glasses. One lens polarises in one direction and the other in the opposite one. The image to be viewed consists of offset images projected with opposite polarisations, so the vertically polarised lens allows that eye to see the vertically polarised image, and the horizontally polarised lens allows the other eye to view the horizontally polarised image.

A third way is to use alternate frame sequencing. Left eye and right eye images are projected simultaneously and the viewer wears special LCD glasses which open and close each lens in sequence with the projected image. The glasses can be controlled using radio signals, and are an ideal candidate for Bluetooth technology. In fact Bluetooth 3D Glasses were unveiled at the CES show.

Naturally, wearing specialised glasses has its drawbacks, and the most sought after 3-D technologies are those that do not rely on such devices. Several such technologies have been developed and together they are referred to as auto-stereoscopy.

The most common of these uses lenticular lenses, which are lenses that vary in magnification depending on the angle from which they are viewed, and parallax barriers which allow each eye to see a different image. Alternatively eye tracking can be used to ensure that the appropriate images are displayed to each eye.

3-D TV Models

The first High Definition 3-D TVs were produced for business, and were far too expensive to be considered appropriate for domestic use. They were manufactured by Philips and used WOWvx technology. This technology is auto-stereoscopic and does not necessitate wearing glasses. It uses a variation of the lenticular lens technology described above. Philips has now withdrawn from future developments of the technology until a glasses-free 3-D TV format is agreed amongst the major manufacturers.

Now all the major TV manufacturers have demonstration 3-D TV’s and they were unveiled at the Consumer Electronics Show in Las Vegas in January 2010. Amongst the manufactures showcasing their new 3-D models were Samsung, Sony, Panasonic and LG. Unfortunately all of these use alternate frame sequencing technologies as described above and glasses must be worn to experience the 3-D effect.

It is expected that these will be available commercially in the US early in 2010 and in Europe a little later. It is anticipated that almost four million will be sold in the first year.

Naturally there is no point in having a 3-D TV if there are no 3-D broadcasts. So far significant progress has been made in this direction: the Discovery channel is teeming up with Sony and IMAX to provide 3-D broadcasts; BSkyB in the UK will be launching a 3-D service in late 2010; ESPN have announced that they intend to broadcast nearly 100 sports events in 3-D; and other plans to broadcast 3-d are in the pipeline.

The Future: Auto-stereoscopic TV in the home?

The major drawback with current 3-D TV models is the need to wear special glasses, so will it ever be possible to do without them? In fact the answer to this is probably. As was mentioned above, the technology has already been demonstrated, but the problem is that the price is simply prohibitive and, until a standard can be agreed amongst manufacturers and broadcasters, currently outside academia any further developments are on hold.

We think there is a danger that the current 3-D TVs which require that viewers wear special glasses will end up as a short-term gimmick and, once the novelty has worn off, it could be a commercial failure. This could either hasten the development of 3-D TV without glasses or is could delay it. Only time will tell.