TV Types: which one do you like?

There are 4 commoms TV types that you have to consider; all of them have their pros and cons, so lets check them out...

If you aren’t interested in High Definition TV or that new 16:9 "widescreen" picture shape (the aspect ratio of normal TV is 4:3), you can get a simple analog set and save a lot of money.

A conventional analog CRT set will still let you enjoy superb picture quality from a DVD player, but it won’t display an HDTV image, nor will it show the film-like images possible from a DVD player with "progressive-scan" outputs, which eliminate visible scanning lines. To get that film-like image, you have to move up to a digital TV that’s HDTV-capable, and if you want the 16:9 widescreen picture tube, the set will run you a couple of grand or more. But old or not, CRT sets can deliver stunning high-definition images. Maximum screen size is limited to about 40 inches, and if you plan to pull in HDTV signals over the air, you’ll need the accessory HDTV tuner, which runs an extra $500 to $1,000. Most digital cable boxes and small dish satellite tuners have the option of HDTV reception (with an upgraded dish).

Talked about for decades as the Next Big Thing, the proverbial flat panel wall-mountable television displays only a few inches thick has officially arrived, and now there is a group of new TV display technologies to choose from, all with improvements and some disadvantages. Herewith, a condensed guide to the new displays.

Unquestionably the coolest TV around--it’s 3 to 5 inches thick and from 32 inches to 60 inches in diagonal screen size--the flat plasma panel uses a transparent electrode behind a glass sandwich that encases gas-filled cells coated with red, green and blue phosphors (a second electrode is behind the phosphors). The electrodes excite the gas, which then stimulates the red, green and blue phosphors to glow in the appropriate colors. Plasma panels are so bright you can view them in a well-lighted room, and they remain clear and bright over a wide viewing angle. (By the way, since "pixel" may arise in this discussion, a pixel is a "picture element" that comprises a three-phosphor group) .

Downsides? While true blacks from plasmas are improving a lot, they may be subject to burn-in if you’re not careful (an image permanently imprinted on the screen), and they’re expensive -- from $3,200US for a 42-inch diagonal HDTV to multiples of that price for larger screen sizes. If you want a bigger screen, look at your bank account--a high-definition (HDTV) plasma panel 50 inches or larger will be $7,500US and up. Prices are expected to fall by about 1/3 every two years.

The liquid-crystal display (LCD) has been around for more than 20 years. If you’ve seen a laptop computer, you’re familiar with an LCD flat panel. It uses an array of thin-film transistors (TFT) that power liquid-crystal-filled red, green and blue cells (again, each making up one pixel) in a glass sandwich.

LCD panels have to have a light source to operate. When the transistors supply voltage, the liquid crystals untwist, allowing varying amounts of light to shine through them. As such they’re also easily adapted to a projector, where a bright lamp is focused through the LCD chip.

LCD flat panels are very popular in smaller screen sizes (plasmas take over at about 40 inches), with prices starting around $2000 for 26-inch screens.

LCD flat panels and projectors have trouble producing a true black, because whether in a flat panel or projector, light always has to pass through the LCD chip. (Unlike a plasma display, the LCD panel doesn’t originate light.) And as you’ve likely noticed with laptop computer displays, they aren’t viewable over as wide an angle. If low in resolution or clarity, or if you sit too close, LCD images can exhibit a "screen-door" effect, where each pixel becomes visible. But like DLP projectors (see below) LCD models are quite compact and lightweight, often 10 pounds or less. They also require regular maintenance, including new bulbs after approximately 2000 hours.

Apart from the flat-panel plasma displays, digital light processing (DLP) chips are the newest and most talked about TV technologies. At the heart of all DLP devices is a 16:9 digital micro-mirror chip made by Texas Instruments. A high-intensity bulb is focused with a lens towards the DLP chip, whose surface is covered with nearly a million tiny pivoting mirrors that reflect light from the bulb onto a screen. Color is derived by filtering the light through a color wheel. The DLP chip is a huge advantage in a rear-projection set because the set can be made relatively thin (about 14 inches) and lightweight (70 lb.) compared to cumbersome CRT sets. DLP rear-projection sets can be very bright with excellent high-definition clarity and cost about.

for a 50-inch screen. Used in a front projector, DLP is remarkably compact (the size and weight of a slide projector) and capable of quite bright, contrasty images with blacks that are better than plasma or LCD-based displays, almost as good as CRT blacks. And because the mirrors in the chip are integral to it, DLP projectors don’t have convergence problems, nor are they subject to burn-in of images like plasma panels. DLP is still an emerging technology and some images can be subject to a "rainbow effect" if you glance quickly at the screen (fewer than 10% are bothered by it). Many DLP front projectors range in price from as little as $1,500US (for enhanced definition, not HD) to $6,000, depending on the projectors' HDTV capabilities. DLP technology also requires regular maintenance. Bulb life is about 2,000 hours (depending on your projector) and the bulbs cost about $450. For an affordable compact device free of convergence adjustments, DLP may well be the future of front and rear TV projection.