3D technology was out in force at the Display Week conference sponsored
by the Society for Information Display (SID) last week in Los Angeles. I was particularly impressed by the range of 3D techniques that
seem to be coming over the next few months, including a new “active
shutter glass” system coming from Samsung and RealD and a few
demonstrations of “glasses-free” sets.
Today’s home 3D TVs mainly come in two flavors. Active shutter glasses
were the first technology to be introduced on a wide scale, combined
with multiple kinds of display technology–LCD panels, plasma displays,
and DLP projectors. In the LCD world, it works by having a relatively
high frequency TV alternate the image each cycle and having the glasses
tuned to that cycle, so that the images alternate between your left
and right eye. This is still the most common type of 3D TV, supported
by lines of TVs from Samsung, Sony, and others. Panasonic makes a plasma, which I think may have the best looking 3D, partly because
plasma panels are faster.
For this technology, Samsung LCD was showing off two nice advancements.
The first was a 55-inch set running at 480 Hz, and I have to say the higher speed really did seem to make a difference in the demo, reducing crosstalk.
The second was 70-inch, 240Hz set but this one running in “UD” (4k by 2k), where it delivers higher resolution. This was also notable for being manufactured on an experimental oxide semiconductor process.
The big current alternative, which was shown at CES, but is just starting to show up in retail sets, is the film patterned retarder (FPR) technology that is being pushed by LG Display and used in sets from LG Electronics, Vizio, and others. In this technology, the horizontal lines on the display are polarized in alternating directions and a viewer uses passive polarized glasses.
LG was showing demonstrations how the FPR technology has less flicker than what it calls “shutter glasses (SG)” technology and works even at a 90 degree viewing angle.
It also showed how the passive glasses (top) were much simpler than the shutter glasses (bottom).
Samsung and other competitors say the FPR technology effectively cuts the resolution of the image going to each eye by half (to 1920 by 540) since each eye only sees every other line when you are wearing the glasses. But LG countered by saying the brain puts the two eyes together, so you see a full-resolution image. I have to say I find the passive glasses solutions to be easier to watch than most current active-glasses LCD solutions.
But Samsung Electronics seems to be hedging its bets a bit, announcing a partnership with RealD for a different technology that they are calling “active shutter glass.” In this case, a 240Hz display includes a specialized polarization filter, which consists of two thin pieces of glass with a liquid crystal in between that changes phase in synchronization with the left and right eye images. Thus, the shutter is on the glass in the display, while the glasses are passive. This uses circular polarization, just like RealD’s popular cinema solution, so it uses the same glasses you may be familiar with from the movies.
Samsung and RealD were each showing three versions of this technology: a 46-inch 240 Hz TV, 23-inch 120Hz monitor, and a 17.3-inch 120 Hz notebook. Samsung has said it plans on shipping the technology in early 2012, and RealD, as a licensing company, says it wants to make the technology as ubiquitous as possible. (RealD also has an add-on for projectors with similar technology, though that was just a “technology demonstration.” )
Most of the autostereoscopic or “glasses-free” 3D displays I saw at the show were smaller displays, but Samsung was showing one 55-inch set.
What made this special is that the set could automatically and very quickly switch between 2D mode when the lens was on and 3D mode when the lens was off. This is important because one can imagine 2D commercials being shown in between 3D content, or the reverse, for example. However, the viewing angle is still not very large, and it looks like this technology is still not where it needs to be for mainstream use.
3D TV may not have the hype it did a year ago, but the technology continues to improve. Perhaps most importantly, the premium for 3D is shrinking, and thus 3D is likely to become just a feature on more and more high-end sets.
