HDTV Update 2008 Page 2
120-Hz Technology: The New 1080p
If 1080p resolution was the flat-panel differentiator last year, 120-Hz technology is what's setting one LCD apart from another in 2008. The use of 120-Hz refresh rates came about as a way to address a common LCD drawback: motion blur, or the perceived smearing of images during fast-moving scenes. Doubling the video frame rate from 60 to 120 Hz can help reduce incidents of blurring.
Why blurring occurs is actually a rather technical discussion; it's related to the fact that most LCDs use a continuously lit backlight, with each frame presented in what's called a "sample and hold" fashion, so that all the pixels are kept lighted for the duration (roughly 60 milliseconds for 60-frame-per-second video) of the entire frame. By contrast, images on CRTs or plasma TVs are "flashed" on screen for short periods before going dark before the next frame is presented; our eyes interpret this series of sequential individual frames as motion. With sample-and-hold, we can perceive the lack of breaks in the light between frames as blurring. That's why motion blur can still occur even in LCDs with very fast claimed response times.
There are several ways to remedy this problem, including the use of flashing backlights, or black-frame insertion, where a black or darker frame, identical to the one before it, is inserted between actual video frames. While this effectively creates frame breaks, it also tends to reduce the image's overall brightness. That's why another frame-insertion technology, called motion-adaptive interpolation, is increasingly being used. With this method, the TV compares prior and succeeding frames, then generates an intermediate frame that's inserted between each of the 60 frames that appear each second on broadcast programming.
Most of the major LCD brands currently reserve 120-Hz technology for their step-up models, often calling it by a proprietary name: Motionflow (Sony), McFi (Samsung), TruMotion (LG), Clear Motion Drive II (JVC), and ClearFrame (Toshiba). But 120-Hz technology will likely become more widespread starting next year, even in lower-priced sets. Budget-priced leader Vizio, for example, is now including its version (Smooth Motion) in its 42- and 47-inch 1080p XVT-series sets, which are priced at $1,500 and $1,900, respectively.
Making the situation a bit more confusing is that many companies are marrying 120-Hz technology with video processing circuitry designed to reduce the jerkiness - or judder - that can occur with 3:2 pulldown, which is used to convert 24-fps film-based content to 30/60-fps video. Not surprisingly, companies also tend to give these anti-judder technologies proprietary names, such as Bravia Engine (Sony), Reel120 (Hitachi), and AutoMotion Plus (Samsung). One additional benefit of 120-Hz technology is that it has the potential for better display of 24-fps film content since it's already an even multiple of 120 (24 x 5). With so-called 5:5 pulldown, all the frames are displayed for the same amount of time, avoiding the jerkiness that can come with the uneven cadences of 3:2 pulldown.
Untethered TV and the Internet
Although "wireless" TVs aren't new - portable models have been around for a while and Samsung's FP-T5894W, which uses 802.lln technology, has been out for more than a year now - it's likely to be a growing trend going forward. But companies are using different wireless protocols, including 802.11n to WirelessHD, Wireless HDMI (Ultra Wide Band, or UWB), and Wireless HD.
For example, LG's 50- and 60-inch PG70- series plasmas, and 47- and 52-inch LG71-series LCD TVs, are based on the 802.11n wireless specification. The plasmas are "wireless-ready" - they need an optional transmitter module - while the LCD sets have built-in wireless and come with a wireless receiver. Panasonic plans to incorporate WirelessHD, developed by SiBeam, which uses the 60-GHz RF band to send signals from a transmitter to a receiver, while Sony offers a Bravia Wireless Link module that attaches to its Bravia LCD TVs with a digital media extender (DMeX) port. Toshiba will have a wireless Regza, using Wireless HDMI later this year. Westinghouse, which is using CWave's UWB wireless in some commercial models, has said it will offer wireless consumer TVs with UWB some time next year. The company estimates that wireless sets will carry about a $200 premium over non-wireless 1080p models.
Bypassing computers and bringing Internet content directly to TVs has been another goal for a growing number of companies. For example, Sony's Bravia TVs use an optional $300 Internet module, called the Bravia Internet Video Link, to access content from partners including CBS, Yahoo, Sports Illustrated, YouTube, and Wired.com. Sony also announced that this fall it will offer the Sony Pictures summer hit, Hancock, as an Internet download to Web-enabled Bravia owners before distributing it on cable, satellite, DVD, or Blu-ray Disc.
Other companies are striking similar content deals. Panasonic's Z850 Viera-series plasmas include Viera Cast, which provides access to content from YouTube, Google's Picasa online photo albums, and Bloomberg. Owners of Samsung's Series 6 or Series 7 LCD and plasma TVs, which include an Ethernet port, have access to weather, news, sports, and stock information from USA Today. Sharp's Aquos Net, available in its SE94 series LCDs, gives users access to select Web-based content plus real-time customer support. You can create onscreen widgets that display traffic info, weather forecasts, stock quotes, news and entertainment headlines, and high-definition artwork and images from various content partners, including WeatherBug and NBC Universal.
Lights on the Horizon
Backed by promises of better contrast and deeper black levels, a wider range of colors, longer life, and increased energy efficiency, LEDs and lasers could eventually replace CCFL (Cold Cathode Fluorescent Lamps) in LCD TVs, and UHP bulbs in RPTVs.
Samsung has been at the forefront of LED use. Along with offering several RPTVs with LED backlights, its 81-series LCD models use LED backlights with local dimming, a technology that lets certain areas of the screen to be dimmed while others remain bright. The company is now selling a 70-inch model in Korea. LG's 47-inch LG75 LCD set is the company's first to use an LED backlight, which consists of 128 separate zones that can be dimmed independently.
Sony will use its own Triluminous LED backlighting with local dimming in its flagship XBR8 models, offered in 46- and 55-inch screen sizes. Sony claims the three-colored LED backlight has purer colors than single white LED backlights. The company has also shown a 70-inch XBR3 LCD TV with the Triluminous backlight, albeit without local dimming.
Thanks to very high brightness and an expanded (200% of NTSC) color space, lasers have been discussed as backlights for several years, but bringing them to market has been difficult (and expensive). After several false starts, it appears that Mitsubishi is finally ready to release its first laser-lit rear-projection DLP sets, dubbed LaserVue TV. A 65-inch model is slated for fall of this year, followed by a 73-inch version. Mitsubishi claims that a laser-based light source can produce twice the colors of current HDTVs, using just half the power. The sets, just 10 inches deep, are expected to carry prices comparable to similarly sized flat-panel models.
Given the recent wave of 3-D movies hitting theaters, 3-D could well be the TV buzzword for 2009, at least if Samsung and Mitsubishi have anything to say about it. Both companies are aggressively using 3-D capability to extend the life of rear-projection DLP; Samsung also offers two 3-D plasmas, the first 3-D flat-panel TVs we've seen. Samsung is partnering with game developer Electronic Arts to produce 3-D games, and says it's talking to Hollywood studios for 3-D movies. Mitsubishi has teamed up with graphics-card company Nvidia and specialty computer supplier Aspen Media to promote 3-D gaming, with the eventual goal of offering a bundled system. Initially, Mitsubishi will sell 3-D-capable TVs, and Aspen will work to integrate Nvidia's 3-D graphics cards into its media servers.
The major stumbling block is that most of the content needs to be played on a fairly powerful Media Center PC with a robust graphics card. The TVs work with 3-D shutter glasses, which are available from several suppliers, including TriDef, which also makes software that can transform 2-D content into quasi-3-D. But Mitsubishi has talked about a Blu-ray Disc player that can convert 2-D images to 3-D on the fly, and a company called TDVision recently showed a 3-D system that uses standard Blu-ray Discs. To further the development of 3-D technology in the home, a consortium called the 3D@Home Consortium has been formed, with members including Intel, Samsung, Sony, Philips, Mitsubishi, Disney, and Universal. But it might be the release of the first 3-D Blu-ray title, Hannah Montana & Miley Cyrus: Best of Both Worlds 3-D Concert, that causes a new generation to catch the 3-D bug. The disc comes with inexpensive 3-D glasses.
Other companies working on 3-D displays include Hyundai, which is now selling a 46-inch 3-D LCD model (that uses the TriDef technology) in Japan, and Philips, which has been working on 3-D's Holy Grail - a set that doesn't require special glasses - since 2006. It says a 52-inch LCD model could be ready by the end of the year.
So far, Japan has one advantage that we still lack - 3-D programs are now being broadcast on cable four times a day, despite there being few sets that can display them. Given how long it took for HDTV to happen here, I'm not holding my breath.