3D HDTV

With the success of the 3D feature Avatar, 3D for the home television was a heavily promoted technology at the 2010 Consumer Electronics Show in Las Vegas. The current “stereoscopic” vision 3D HDTV technology being rolled out manufacturers has greater color reproduction accuracy and achieves Full HD resolution for both eyes with the Blu-ray standard. Driving manufacturers 3D enthusiasm are forecasts such as one from Display Search of 3D panels having an annual growth rate of 38 percent and reaching a valuation of $22 billion by 2018. The scope for 3D capability is wide as it can be applied to a range of display technologies including LCD, LED LCD, plasma, RPTV (rear projection) and front projection. For once manufacturers seem to be in agreement with compliance to the Blu-ray standard negating the likelihood of a format war such as that with the introduction of DVDs.

Samsung C7000 240Hz 3D LED LCD HDTV

Current 3D Technology

Hopefully most readers will have seen a recent 3D feature film and will appreciate what current 3D is like. For those who don’t, it’s important to understand that it is not holographic in nature such as in Star Wars – A New Hope where R2D2 projects a hologram of Princess Leia. If you change your perspective by moving you will not see a different aspect of the image – it will remain the same.

The current 3D technology being used by HDTV manufacturers is a big improvement on the older color encoded 3D format known as anaglyphic. This process color encodes two images to create a single frame and colored glasses (one red and one green/cyan) are used to separate the two images and produce a 3D effect. Perhaps the best thing that can be said about this 3D process is that the paper glasses were a fraction of the cost of the present ones. In the left had pane of the image below you can see the current 3D cinema process where polarizing filter glasses are combined with, in this case, a twin lens Sony projector or a RealD Cinema projector with an active polarizing filter. This system hasn’t been used by HDTV manufacturers because of the brightness loss and color shift resulting from the polarizing glasses.

There are technologies existing that don’t require wearing glasses such as Philips’ WOWvx 3D technology which we reviewed a couple of years ago. The technology has generally been known as autostereoscopic 3D and has been characterized as requiring the trade off of image resolution to create a suitably large number of viewing zones over a wide field in front of the display.

FHD3D – Full HD (1080p) 3D HDTV

Full HD (1080p – 1920×1080 pixels) resolution 3D (FHD3D) is technically termed “stereoscopic” vision, is based on each eye being exposed to slightly different perspectives (left and right eye perspectives as in the images above and below). Our brain works the magic of fusing the images together into a single image (just as they do with our normal vision) with perceived depth. Active glasses which are synchronized to the HDTV which displays a sequence of left and right eye perspective frames. The LCD shutter system alternately covers and exposes each eye giving them the correct perspective view thus providing the 3-D viewing experience. The shutters blink rapidly enough to avoid any flicker being noticed. Synchronization of the HDTV and the shutter glasses is achieved by an infrared or wireless synchronization signal from an emitter embedded in the bezel of the TV.

With left and right perspective images (frames) required compared to a single frame of 2D video, the bandwidth required is doubled. Consequently, 3D film based content is recorded at 48 frames per second (fps) compared to the standard 24 fps for 2D.

3D HDTV Glasses

One needs to be careful with compatibility of 3D glasses and HDTVs as there is unfortunately no standardized communication protocol. You can get glasses with replaceable or rechargeable batteries and can expect at least 75 hours or more for a full charge.

The image below shows Samsung rechargeable, battery and children’s 3D glasses (available in blue also). Children’s glasses are required because of the smaller distance between their eyes which must be compensated for.

HDMI for 3D

News that the new HDMI 1.4 specification introduces support for stereoscopic 3D yet 3D HDTVs are selling with HDMI v1.3 has introduced some confusion. In fact, the HDMI software used has the software for 3D support but, as it does not have all the components of v1.4 it is still labeled as v1.3 as this is the version it supports fully. A problem could arise if the manufacturer has used some proprietary software for 3D processing so, care needs to be taken if you do not have a brand match between components. Both HDMI versions 1.3 and 1.4 have the bandwidth (10.2 Gbps) to handle the dual 3D frames for Full HD resolution.

Once v1.4 of HDMI is commonly available stereoscopic 3D capability will simply be a matter of checking for this standard.

3D Content

A prime source of 3D content for the near future will be Blu-ray 3D discs which comply with the recently announced Blu-ray 3D standard. The specification supports 2D disc playback in 3D players and the 2D playback of Blu-ray 3D discs on existing Blu-ray Disc players.
Numerous 3D ready HDTVs (including Samsung and Toshiba’s upcoming Cell TVs) have a 2D to 3D converter built in to compensate for the current lack of 3D media. Reports are fairly consistent however, that the result is inferior to specifically produced 3D content.

Stereo (3D) Blindness

The recent popularity of 3D in cinemas has interestingly prompted some patrons to visit the optometrist because they couldn’t see 3D or the experience was uncomfortable and associated with headaches. They likely discovered they had stereo blindness which affects what is a contentious estimate of 2 to 12 percent of the population. Stereo blindness affects more than seeing 3D including reading and driving and sports. It is something worth investigating as it is treatable in most cases with simple remedies such as vision therapy. Use this quick online depth perception test if you think you may have a problem.