SAN FRANCISCO (11/24/2003) - You have 800 digital TV channels, a Media Center PC and a DVD player, but you're still using 50-year-old display technology? If so, chances are you're ready for something bigger -- and maybe sleeker -- than the bulky cathode-ray tube that has brought video into your life for so long.
Once-exotic alternatives based on plasma, LCD, and DLP (Digital Light Processing) technology are becoming both more common and more affordable -- and in the realm of big, wide-screen TV sets and monitors, they're threatening to push CRT-based designs aside. Economy of size drives these displays' appeal. Large rear-projection CRTs, which once were the only remotely affordable big-screen displays, weigh hundreds of pounds and dwarf most other living-room furniture.
Big-screen alternatives such as plasma panels, direct-view and rear-projection LCD sets, rear-projection DLP displays, and even digital projectors are much more compact; a flat-panel TV can be mounted on a wall like a painting.
Prices for these newer-tech displays are dropping rapidly. You can pay as little as US$1,000 for a digital projector or as little as US$3,000 for a 42-inch plasma panel. Nevertheless, the newer display devices generally cost more than their CRT cousins. But David Mentley of display research firm ISuppli/Stanford Resources says that within just a year or two, rear-projection DLP sets may become cheaper than CRTs of comparable size.
Price range: $3,000 to $30,000 for screen sizes ranging from 42 to 61 inches.
Overview: Best if you want a wall-hanging or a relatively inconspicuous display for television and movie viewing that can perform well in strong room lighting -- especially if cost is not a great concern. Heavy PC users and gamers should look elsewhere.
Details: Sleek and sexy, these wall-mountable panels are the embodiment of futuristic television. Top-of-the-line plasma screens can deliver gorgeous high-definition pictures. And because they are only a few inches thick and (unlike some LCDs) can be viewed from well off to the sides without loss of image quality, they are extremely versatile. Although the big downside to plasma has been price, some 42-inch plasma models now cost only about $3,000 -- but for that bargain price you don't get HDTV resolution.
With plasma screens, you tend to get what you pay for. Plasma displays in general struggle to produce deep black tones, and the images in some inexpensive plasma displays look washed out. You'll pay more for higher contrast and resolution, but if you can't afford to splurge for both, a high-contrast, low-resolution picture will usually appear to have more detail and better color saturation than a low-contrast, high-resolution image. Look for a contrast ratio of 1500:1 rather than 800:1. Contrast-ratio specifications are often exaggerated, however, so try to look at a display before you buy it, bearing in mind that display controls and signal quality strongly influence the quality of the image.
Almost all plasma displays are wide-screen units with a 16:9 aspect ratio. Like CRTs, they use phosphors to generate light, which means that phosphor burn-in can be an issue if you watch a lot of TV or play games in a narrower 4:3 aspect ratio. (Burn-in produces lingering, permanent or semipermanent ghosts of static images that have been displayed for long periods of time.) Stretch modes, which allow any image to fill the screen, can help (at the expense of distorting the picture somewhat); and many plasma displays now come with other features designed to prevent burn-in. Also, you can substantially reduce the risk of burn-in (and extend display life) by using moderate brightness and contrast control settings; you don't have to max out today's high-contrast panels to obtain vivid pictures.
Price range: Direct-view LCD, $4,000 to $6,000 for 30- to 40-inch screens; rear-projection LCD, $3,000 to $5,000 for 40- to 60-inch screens.
Overview: Direct-view LCDs are excellent as combination TV/PC monitors, but slow response times on some older models may frustrate users who play fast-action games. Good for flat-panel TVs in screen sizes smaller than the available plasma models.
Details: Direct-view LCD units currently top out at 40 inches diagonal (larger screens are coming in the next few years). Since plasmas start at 37 inches, LCD is the only choice for smaller flat-panel displays. LCDs with screens measuring 30 inches and up are almost all wide-screen, 16:9 displays, and they are costly compared with rear-projection alternatives. But again, prices are expected to drop as the supply of larger LCD panels grows.
Direct-view LCDs are generally more suitable than other big-screen options for dual PC-TV use; they frequently come with stands for desktops and are better equipped to handle a wide range of PC monitor resolutions than are plasmas and rear-projection TVs. Because they don't use phosphors, LCDs are immune to burn-in. Although poor response time on older LCDs made them undesirable choices for viewing action films or for playing fast-moving games, newer models tout faster response times, so you'll see the difference only in high-end games -- if at all. The contrast ratio on LCDs tends to be low compared with that of other display technologies -- 500:1 is typical -- so images may look washed out on some.
Several companies are also using LCD technology for big (up to 60-inch), wide-screen, rear-projection HDTV sets. These are tabletop models: A typical 52-inch set will weigh a little over 100 pounds and will measure less than 40 inches tall and 18 inches deep; that's shallower than most 27-inch CRT sets but much deeper than direct-view LCD panels or plasma screens. Like direct-view LCD sets, rear-projection LCD models tend to be somewhat weak on contrast. Their viewing angle is in most cases wider than that of CRT rear-projection TVs but narrower than that of direct-view CRTs or plasmas. Prices now almost match the cost of CRT rear-projection TVs of similar size (which will likely vanish from the market as their remaining slight price advantage disappears). But if you're interested in buying a rear-projection LCD screen, consider getting a DLP rear-projection set instead. It may cost a little bit more, but it will usually produce better-looking images.
Price range: $4,000 to $5,500 for a 43- to 61-inch screen.
Overview: Excellent for TV and movie viewing in almost any setting; more affordable than a skinnier LCD or plasma. Good contrast ratios, response time, and color range make DLP the best choice for most serious PC or console gamers.
Details: It's hard to believe that you can produce video images by using thousands of tiny movable mirrors, but that is exactly how DLP sets work. Like LCD rear-projection TVs, DLP sets are shallow (15 to 18 inches thick), wide-screen, tabletop HDTVs that weigh 100 to 125 pounds and are immune to burn-in. Their contrast ratio is better than that of LCD and many plasma models. Picture quality does not deteriorate with age as it does on CRTs and plasmas, brightness is often higher, and color range is frequently broader. If you can't afford plasma, rear-projection DLP is an excellent alternative choice.
Price range: $1,000 to $12,500 for models under 30 pounds.
Overview: Many digital projectors today are small enough and light enough to accommodate temporary home theater setups pretty much anywhere you have room for a screen. Though movies benefit most from big-screen treatment, regular TV and games can look stunning, too. On the other hand, the low-ambient-light requirement and setup hassles (unless you opt for a fixed installation) make projectors less than ideal for everyday living-room use.
Details: Want a really big picture (as in 5 to 10 feet diagonal)? Or maybe a big screen that you can put up quickly when you want it and put away just as easily when you don't? LCD and DLP digital projectors come to the rescue.
Generally speaking -- and admittedly those are dangerous words, given the range of manufacturers and models -- LCD projectors offer somewhat lower contrast than do DLP models (especially the ones with higher-end three-chip designs), but DLP models tend to cost more. For either type, key considerations include the range of acceptable mounting distances from the screen and the maximum image sizes for those distances. Both types use a single adjustable lens and need none of the critical tube-convergence adjustments required with CRT-based projectors, so setup tends to be relatively simple.
But even though LCD and DLP projectors today generate significantly more light than CRT models, their pictures will still wash out unacceptably if you don't keep strong sunlight or room lighting away from the screen -- and as a result, they are impractical for everyday, living-room TV use. Also, low-resolution images will have an obviously grainy appearance when blown up very large. So if your goal is a really big picture, consider a home theater projector that supports HDTV resolution. These go for as little as $3,000.
If you decide to purchase a projector, don't forget to check the fan noise. A projector that is acceptable for business presentations may be annoyingly loud for movie watching.
You will probably want to get a good screen, too. Prices start at about $170 for a 6-foot, 4:3 screen and at about $300 for an 8-foot, 16:9 screen.
And if you'd like to avoid struggling with setup hassles every time you want to watch a DVD movie, consider investing in a ceiling mount: Basic models sell for $120 to $200.
Whichever display technology you choose, you'll be dealing with a fixed-pixel device. Unlike a CRT display, which can change the size of its pixels, a fixed-pixel display uses a grid of unalterable pixels that can't display different resolutions. If you change the graphics resolution on a computer equipped with a CRT monitor, the monitor will change the number and thickness of lines scanned. In order for a fixed-pixel device such as a laptop's LCD screen to display a nonnative resolution, it must interpolate the image data to fit the grid -- a process known as scaling. (If the desired resolution is smaller than the native resolution, a fixed-pixel display can simply refrain from using all its pixels, leaving a frame of black.)
Today there are multiple TV image formats, so much or all of what you view on a digital display will have to be scaled from its native resolution. Mediocre scaling technology thus can significantly degrade picture quality. Fortunately, decent scaling has become far more affordable in recent years. And the best fixed-pixel displays tend naturally to look sharper than CRT screens. But because a display's built-in scaler can have such a big impact on your viewing experience, test a variety of video sources -- from cable or satellite TV to DVD to HDTV -- before you buy.
Also compare the video outputs on the devices that will feed the display -- your DVD player, VCR, and so forth -- with the number and type of inputs on the display. If you have an external HDTV tuner, you'll need at least one input for it -- RGB, wideband component video, or (if possible) DVI or HDMI. DVI is the digital input standard used for computer monitors. HDMI is essentially DVI with added lines to carry digital audio along with the video; in addition, it has HDCP (High-bandwidth Digital Content Protection) encryption, an industry standard that combats piracy of multimedia content.
Long-term, the best input to have is an HDCP-compliant DVI or HDMI input, since future broadcasts may require HDCP encryption between external tuners and displays.
If you want to hook up a progressive-scan DVD player, your display must also have an available component-video input. And if you want to connect a computer to the display, make sure it has a VGA input compatible with your PC.
Finally, these displays often have cooling fans to dissipate heat. Check the noise level. It may not matter in a meeting room, but it will in your home theater. When you're investing $1,000 or more in a living-room display, you want to nail down every detail.
Digital TV: Getting set for HDTV
American TV is getting better (well, in terms of technology, anyway), and it's turning digital. Not all large-screen TVs support the higher resolutions known as HDTV (high-definition television), and right now relatively little TV is HDTV. But if you're shopping for a big-screen TV, you'll want to consider getting one that supports HDTV, if only for future-proofing.
Today's North American TV system is called NTSC, after the National Television System Committee that spawned it. The new digital television system is sometimes referred to as the ATSC system, for the Advanced Television Standards Committee. ATSC TV provides for some 18 transmission formats, ranging from 480i "standard definition" (similar to NTSC) to a pair of HDTV formats, 720p and 1080i. The numbers represent how many active scan lines, or pixel rows, make up each complete video frame. The letters represent whether the frames are created by progressive or interlaced scanning. In progressive scanning, images are scanned left to right to create a full frame of scan lines from top to bottom; with interlaced scanning (which NTSC uses), all the odd-numbered scanned lines are created, after which the even-numbered lines are scanned and nested within the just-created odd-numbered scan lines. Interlacing causes minor picture degradation, such as flickering between adjacent lines, but it permits greater perceived resolutions at lower transmission bandwidths.
Both 720p and 1080i HDTV look superior to NTSC. Which is better? On still images or material with little motion, 1080i should provide more detail. But on fast-motion scenes, such as sports, 720p's rendering of full frames every sixtieth of a second, instead of half-frame fields, should yield a cleaner picture. CBS and NBC have chosen 1080i; ABC and Fox have opted for 720p.
The ATSC standard also provides for two aspect ratios (ratios of display width to display height): the squarish 4:3 familiar from NTSC (and most PC monitors) and wide-screen 16:9, a better match to the human visual field and to movies. The HDTV formats use the wide-screen aspect ratio: 720p is 1280 by 720 pixels, and 1080i is 1920 by 1080 pixels. The 4:3 aspect ratio (640 by 480) of 480i is basically a legacy provision, while 480p's 16:9 ratio is known as EDTV (enhanced-definition television). It resembles the output from a progressive-scan DVD player, but it isn't HDTV.
Sets described as "HD-ready" are capable of HDTV resolutions but have no built-in tuner to receive HD transmissions. To see HDTV on these sets, you'll need an external HDTV tuner, which supports all ATSC formats and costs a minimum of about $400 (more if you want a built-in satellite tuner or other features).