So you want a Big Screen - Comparing Today’s TV Technology

The Super Bowl is fast approaching and that 20-inch TV you’ve been watching since your undergraduate days is looking mighty small and worn out. It’s a good time to move up to a big screen HDTV. Prices are dropping and there are enough options to satisfy just about any budget and room size, from a bathroom to a full-blown entertainment room. The following is a quick primer to help you sort out the choices.

HD—does it really make any difference?
HD (High Definition television) was introduced in 1998 and prices have dropped significantly, but HDTV sets are still more expensive than conventional analog TV’s. So what’s the big deal? Is HDTV worth the extra money?

A conventional TV paints 480 lines on a screen to make the picture. It does this at a very fast rate, 60 passes a second, during which even numbered lines are painted on one pass and odd numbered lines on the next. This means that all 480 lines are painted 30 times a second allowing your brain to processes them as a stable image. This every-other line painting is called interlacing and provides a resolution of 480i (interlaced).

Computer monitors use a process called progressive scan that paints each line in sequence without skipping lines. All 480 lines are painted 60 times a second rather than 30 giving a higher resolution than 480i. SDTV’s, digital TV’s or progressive scan DVD players that use this process, have a resolution of 480p (progressive).

HDTV further increases the number of painted lines using two accepted standards: 780p or 1080i. Videophiles claim that 780p provides a more stable picture, while 1080i gives better resolution, but for the average viewer, there’s no difference between the two. Most HDTV sets have a processor that converts regular TV images into progressive scan, so that even non-HDTV programs are clearer. Most DVD players already use progressive scan, so the combination of DVD and the increased resolution of HDTV offers a particularly clear picture.

What else will you need to view HDTV programming?
HDTV sets with an integrated DVT tuner are capable of receiving over-the-air HD signals with the aid of an outdoor antenna. HDTV “ready” or “compatible,” sets require a separate tuner, but don’t worry. Most households now subscribe to cable or satellite rather than using an antenna, and providers offer an HDTV converter for a minimal cost.

Just because you have an HDTV set, it doesn’t mean that all the programs you receive will be broadcast in HD. The major networks broadcast much of their programming in HD, so, if you have an outdoor antenna, you can watch most local programming in HD. You’ll still need cable or satellite to watch networks like HBO and ESPN, but these providers don’t necessarily offer all the HD programming available. Don’t despair, it’s only a matter of time, particularly if you live in a major metropolitan area, before consistent HD programming is available through a single source. In the meantime, HDTV still offers you a superior performance using any signal.

Wide screen or traditional
TV’s now come in two widths, the traditional 4:3 ratio (four inches of width for every three inches of height) and the newer 16:9. The wider screen allows you to watch movies and see the full screen without letterboxing, those annoying black bars on the top and bottom of the screen. Conversely, 16:9 sets letterbox regular programs on each side.

The reality is that most big screen TV’s are now 16:9 and it’s only a matter of time before virtually all TV’s are wide screen, which will drive an increasing amount of content to wide-screen format.

Picking the TV that is most appropriate for you?
Of course, everyone wants the brand new eighty-inch plasma flat-screen from Samsung, but sometimes you have to be reasonable. Here’s a rundown on the different types of big-screen TV’s that are available and the pros and cons of each.

DIRECT-VIEW CRT
Think of an old-fashioned TV with a picture tube. They’re the most economical option and offer the best overall picture. They have especially strong black levels, which means good depth and quality of dark colors. They provide a good picture from any angle, they can be easily viewed in brightly lit rooms and they have a relatively long lifespan. The major drawback is their size. A 40-inch model, which is the largest size available, can easily weigh as much as 300 pounds and be 26 inches in depth. You can buy a 30-32 inch set for less than $1,000.

REAR-PROJECTION CRT
CRT rear-projection TVs use three Cathode Ray Tubes—red, green and blue—which are aimed together at a focusing lens that bounces the picture off of a mirror. Sizes range from around 40 inches to more than 70. They are relatively low cost, have very good black-levels, and high quality pictures. They are also fairly large size and heavy (a 50 inch set weighs about 180 pounds and is 26 inches deep), they are hard to see in bright rooms, their viewing angle is narrow, and they get out of adjustment easily. A 50-inch model will cost you about $1,500.

REAR-PROJECTION LCD
There are two types of LCD (Liquid Crystal Display) TV’s—rear projection and flat-panel. The rear projection model shines a light through three LCD panels that project red, green and blue moving images. They have a high resolution, and they don’t require regular maintenance like CRT’s. They are also relatively slender and light compared to rear projection CRT’s (16 inches in depth and 130 pounds for a 50 inch set). Their major weakness is poor black levels, but the newer models perform much better in this area. Expect to pay between $2,500 and $3,000 for a 50 inch set.

REAR-PROJECTION DLP
DLP (Digital Light Processing) sets and rear projection LCD’s are hot. Both are slim, relatively lightweight and are very good in bright light. DLP’s use a color wheel that shines red, green and blue lights in rapid succession over a single mirror-covered chip, whose image is then focused by a projection lens. This provides particularly strong contrast. The early models had some problems with “rainbows” where distinct red, green and blue elements flashed on the screen. Improvements to the color wheel have cleared up this problem. A 50 inch model costs around $2,800 to $3,800.

REAR-PROJECTION LCOS

LCOS (Liquid Crystal on Silicon) sets are potentially capable of delivering extremely high resolution, but they are still relatively new and availability is limited. LCOS reflects light on panels or a single panel, rather than passing light through them like LCD’s. This allows for deeper contrast than LCD’s while retaining their low maintenance, slimness and light weight. The downside is that the technology is still developing and there are technical issues to resolve, but there is a lot of excitement about the potential technology. You’ll pay around $3,400 for a 52 inch screen.

FLAT-PANEL PLASMA
Remember the first time you saw an ad for a plasma TV hanging on the wall or free-standing like some sleek work of techno-art? Plasma sets are sexy. They work by shooting ultraviolet rays at a panel coated in phosphor, which makes specks of the phosphor turn red, green or blue. “Unexcited phosphors” stay black, providing high contrast. However, black levels are low and plasmas can suffer from burn-in, similar to a computer monitor. The good news is that plasmas are dropping rapidly in price. Expect to pay $6,000 and more for a 50-inch model.

FLAT-PANEL LCD
Ultra-thin, flat screen LCD’s work well in bright rooms and don’t have problems with burn-in, but their blacks and contrast are still not as good as plasmas. One neat thing is that smaller LCD’s can fit almost anywhere from the front of a refrigerator to a bathroom wall. Unfortunately, they currently max out at about a 40-inch screen size. Expect both size and contrast issues to be worked out in the near future as production steps up. Most experts expect flat-screen LCD’s to virtually eliminate plasmas in the near future. Prices for a 40 inch flat-screen LCD starts at about $4,000.

A few tips
Before plunking down two week’s salary on a new TV, keep a few things in mind:

• Measure the space in which you plan to put the TV and then take the tape measure with you to the store to make sure what you want will fit.
• Take a familiar DVD with you, preferably one with some darkly lit scenes and compare the performance on several different types of sets.
• Don’t buy an HDTV with a built in tuner unless you plan to use an outdoor antenna. It’s cheaper to buy a separate tuner, or rent a conversion box from you cable or satellite provider.
• Check the inputs on the set to make sure it has enough to plug in all your accessories, such as a DVD player, receiver, TiVo, etc.