Tuesday, July 27, 2010

Temporal Resolution and 3D TV

If you are a display engineer and are describing the resolution of a TV set, to this point, there were actually three resolutions to describe: the spatial resolution or dot pitch, the chromatic resolution (brightness, number of colors), and the temporal resolution (response time). As described in my article "Rest in Peace Plasma..." in the latest issue of "High resolution", although these three resolutions are different, they are collectively fungible; you can trade off one for another. Now there is a fourth resolution, depth, where these trade-offs become important; specifically, 3D TV trades off temporal resolution to achieve 3D. Any familiarity with LCD Televisions and you will know that until this point in time temporal resolution has been a precious commodity for LCD technology. Although adequate for most content, the response time of LCDs was at best marginal for fast moving content and now the technology is taxed even more, having to display two distinct images in the same time frame where it previously could only mange one.

Plasma, on the other hand, effectively has effectively unlimited temporal resolution, much faster than human perception. The physics of the technology dictate that it will always be much better than LCD in that respect. The timing of the move to 3D, being initiated by the LCD makers is curious, as Plasma was continuously loosing marketshare to LCD and could have been well on its way to some niche category. However, Plasma's much higher resolution is starting to become noticeable to the general public. Although it is not technically described, this news report from ABC ( http://abclocal.go.com/kfsn/story?section=news/consumer&id=7570356 ) and the source Consumer Reports article highlight that the image smearing that was once only of concern to engineers is made much more noticeable to casual viewers when the display has to do the double duty of displaying two images for 3D. The subtitle to my high resolution article "Rest in Peace Plasma... Not so Fast". 3D has definitely turned the fortunes of Plasma as a technology.