Did you know you can get a plasma HDTV for $1,800? That’s right — TV technology that a few years ago cost more than a Hyundai is now within reach of most middle-class American budgets. Prices for entry-level big-screen HDTVs, including those flat-panel plasmas and LCDs as well as advanced DLP and LCD projectors, are falling at near-terminal velocity and have yet to hit bottom.

Of course, some TV technologies command higher prices than others, and good old rear-projection CRTs (cathode-ray tubes) are still the champs when it comes to dollars per inch of screen size — unless you count front projectors. But the newer TV types like plasma, DLP, and LCD generally represent a better investment than CRTs since they usually produce sharper images, take up far less floor space, and offer more models to choose from. No matter which type of HDTV you choose, we’ve outlined entry-level models and prices at various screen sizes to give you a baseline to work with. But don’t be put off by the words “entry level” — most of these sets include every feature you’ll need.

CRT Rear-Projection

CRT-based rear-projection HDTVs have the biggest screens you can get for the smallest cash outlay. While their bulkier cabinets and generally duller image quality make them less popular than the somewhat more expensive microdisplays, low price keeps them in the game for now. But microdisplays are getting cheaper by the month, and their many advantages are worth the extra cash unless your budget is just too tight to break.

How It Works Each set has three tubes — one each for red, green, and blue. Each tube has a “gun” consisting of a cathode for emitting electron beams and anodes for accelerating them. The beam within each tube is focused on a small screen, causing phosphors within the screen to glow red, green, or blue. Lenses and mirrors combine the individual colors from the tubes and focus them on the TV’s big screen.

Pros
•Less expensive than competing technologies.
•Reliable. CRTs have been in service for more than 50 years.
•Best potential of any technology for deep blacks and clean shadows.

Cons
•Big and heavy.
•CRT projection sets are subject to errors in keeping the three tubes aligned as well as image retention (“burn-in”).
•They don’t hold their picture contrast as well as the other technologies in bright rooms and are usually less sharp looking — but with expensive professional adjustment they can look just as sharp as a microdisplay.

Entry Point: $1,000 At press time, BestBuy.com’s least-expensive big-screen CRT was a 51-inch RCA for $1,099, while a 65-inch Mitsubishi set was selling for $1,799. Both of these sets provide almost exactly one square inch of screen per dollar, the best ratio among HDTVs I surveyed. But we haven’t reviewed any rear-projection CRTs for a while, and with good reason: microdisplays are already more popular than CRT sets, and their smaller cabinets and sharper images are worth the added expense.

DLP, LCD, LCoS Rear-Projection

The biggest thing to hit big-screen HDTV since NFL Sunday Ticket, microdisplay rear-projection encompasses three similar technologies called LCD (liquid-crystal display), DLP (Digital Light Processing), and LCoS (liquid crystal on silicon). You can generally get similar-size microdisplays, regardless of the display technology, for around the same price. These digital big-screens cost about 50% more per square inch of screen than their tube counterparts, but prices are falling faster than ever.

How They Work I call these TVs “digital” because, unlike tube-based analog rear-projectors, microdisplays rely on one or more imaging chips that create a discrete number of onscreen pixels — usually 1,280 x 720 (720p) or 1,920 x 1,080 (1080p). Think of these TVs as projectors in a box — light from a lamp interacts with the chip, mirrors, lenses, and other elements to create an image, which is then projected onto the back of a large screen.

DLP microdisplays use a single chip called a Digital Micromirror Device (DMD), packed with nearly a million mirrors that reflect light from a lamp onto a screen. A rapidly-spinning color wheel infuses the monochromatic image with color for the screen.

LCD-based microdisplays — many of which are now being marketed as “3LCD” — use three chips packed with liquid-crystal-filled cells. The crystals untwist to regulate red, green, or blue light that passes through, and that light is recombined and sent to the screen.

LCoS borrows from both LCD and DLP technology. Like LCD, each silicon chip has liquid crystals that untwist to filter light, and as in DLP, light is reflected off the chip toward a screen. Today’s LCoS displays — including JVC’s popular HD-ILA models and Sony’s SXRD sets — all use three separate chips for red, green, and blue.

Pros
•Microdisplays can produce much brighter images than conventional big-screen CRTs, so their pictures show up better in bright rooms and remain more consistent regardless of viewing angle. DLP and LCoS are typically brighter than LCD rear-projection.
•Sharp picture. Microdisplays don’t need alignment and suffer fewer convergence or geometry errors than tube rear-projection sets. Their discrete pixels generally allow them to display more detailed DVD, high-def, and computer images.
•Unlike with big-screen CRTs, there’s no danger of burn-in.
•Cabinets are lighter and much less bulky — especially in terms of depth — than the big boxes required by CRT sets. Some designs are even slim enough to hang on the wall like a plasma TV.

Cons
•Microdisplays are still more expensive than the same-size CRT sets.
•Unlike tube sets, microdisplays still can’t achieve a true black, which is particularly important when watching movies in darkened rooms or when watching a program with dark images. But the best microdisplays do such a good job with blacks that any flaws will only be apparent to highly trained viewers.
•DLPs are prone to a “rainbow” effect. Although the color wheel that separates the white light spins very fast, you might see streaks of primary color if you look closely enough or blink at just the right moment. But not all viewers will notice this.
•LCDs can exhibit a “screen-door” effect, where the pixel grid becomes visible when you sit near the screen.
•The lamps burn out. Typical lamps last 3,000 hours and cost around $300 to replace.

Entry Point: $1,500 I found a 42-inch Samsung DLP selling for $1,499, but the real value starts at the 50-inch and larger screen sizes. Models like the 52-inch JVC HD-52Z575 LCoS set we reviewed in January and the Toshiba 52HDM94 DLP model from the June issue were selling for around $1,800 when I checked. (Bargain hunters: it pays to seek out older models.) Among current models, a good example is the 50-inch DLP-driven 50LPW175 from RCA, which costs $2,299 at Best Buy. Larger sizes offer even more picture for your buck. JVC has a 61-inch LCoS set for $2,700, which works out to $1.70 per square inch of screen.

Flat-Panel LCD

If you’re looking for the best value at 37 to 42 inches, you might find yourself struggling with the old question of “plasma vs. LCD?” But among big-screen TVs, plasma is the clear value winner — at least for now. On the other hand, LCD prices have been dropping at a phenomenal pace and show no signs of slowing down. Also, aggressive panel manufacturers in Korea and Taiwan are bringing ever more factories online, producing ever-larger “motherglass.” In short, economies of scale will catch up with plasma, and by next year LCD will mount a serious challenge at the 42-inch size.

How It Works A matrix of thin-film transistors (TFTs) supplies voltage to liquid crystal-filled cells sandwiched between two sheets of glass. As with plasma panels, a trio of red, green, and blue cells make up one pixel, but each uses a colored filter instead of phosphors to create a color. When hit with an electrical charge, the crystals “untwist” to filter light generated by a lamp behind the screen.

Pros
•Only a few inches deep.
•Higher resolution than plasma at similar screen sizes.
•Uses less power, runs cooler, and weighs less than plasma.
•No danger of burn-in.

Cons
•More expensive than similar-sized plasmas.
•Of the fixed-pixel technologies, LCD has the most trouble with blacks. Some light always passes through, even when the crystals are in an untwisted state, so the best black is usually a very dark gray.
•Because of how light goes through the cells, LCD flat-panel displays usually have narrower viewing angles than plasma TVs.
•Compared with DLP, LCoS, or plasma, LCDs require more space between pixels, which can result in a visible screen-door effect.

Entry point: $1,500 A quick look at current prices proved that flat-panel LCD isn’t yet a big-screen contender. The entry-level 37-inch size barely qualifies as “big-screen,” but models from no-name brands like Syntax Olevia cost about $1,500, while major-label sets from Sharp and others run closer to $2,000. I found entry-level 42-inch models from Philips and others selling for around $3,700 — that’s $4.92 per square inch of screen, if you’re counting. But make no mistake — large-screen LCDs will reach plasma price levels very soon.

Flat-Panel Plasma

I bet you never thought plasma would be included in an article about affordable big-screen HDTVs, but these coveted sets are getting cheaper fast, especially in the popular 42-inch size. Despite the plummeting prices of flat-panel LCDs, plasmas are still a better buy and generally outperform LCD flat panels for demanding home theater viewing.

How It Works Each pixel in a plasma display consists of three gas-filled cells coated with red, green, or blue phosphors. Electrodes above and below the cells (the top electrode layer is transparent) jolt them with varying amounts of voltage. This excites the gas in the cells, stimulating the phosphors to produce colored light.

Pros
•Slim design and large screen size.
•Uniformly bright picture over a wide viewing angle — even in a brightly lit room.
•Excellent image quality, especially compared with LCD. Plasmas use phosphors to produce color, just like CRTs, resulting in excellent saturation and natural hues.
•While performance on dark scenes varies widely, some models approach CRT-level blacks.

Cons
•Still expensive — especially in screen sizes 50 inches and larger. • Lower resolution than LCDs, causing slightly softer HDTV images.
•Subject to burn-in, where an image becomes permanently etched onto the screen. But this won’t happen unless you leave a bright stationary picture on the screen for hours at a time, and recent research suggests these effects might be reversible. Newer models have features to prevent burn-in, like a pixel orbiter, which exercises pixels by slowly shifting an image around the display.

Entry Point: $1,800 Plasmas start at 37 inches, but the least expensive come in the ubiquitous 42-inch screen size, which also provides the best value. Lower-resolution EDTVs are the entry-level here, and though we haven’t reviewed any recently, Panasonic has a 42-inch set that sells for $1,600 (about $2 per square inch). September’s “Plasma for Less” featured a trio of “bargain” high-rez models, and Dell’s $2,600 W4200HD was the clear winner. Vizio recently slashed the price of its 50-inch plasma HDTV to an amazing $2,999. (But we haven’t reviewed it so can’t vouch for its performance.)

Front Projectors

When it comes to dollar per square inch of screen size, you can’t beat a front projector. These things easily produce images more than 6 feet wide. Many DVD-resolution models cost less than $1,000, while you can get some high-def LCD models for less than $2,000.

How It Works Whether DLP or LCD, a budget projector relies on a powerful lamp that interacts with an imaging chip containing a certain number of pixels. Unlike microdisplays, many budget front projectors have EDTV resolution (852 x 480), while step-up HDTV models have a higher pixel count (typically 1,280 x 720).

Pros
•Huge images
•Portable. Unlike every other big-screen technology, a small projector can be stored in a closet when not in use and easily taken to another room, over to a friend’s house, or even on your next RV odyssey.

Cons
•Projectors need a darkened room to look good — or even show a recognizable picture at all.
•At a minimum, you need a big patch of light-colored wall. For optimum image quality, you need a screen, which will cost at least a few hundred bucks.
•Budget projectors use LCD or DLP technology and are subject to many of the same limitations as microdisplays.

Entry Point: $1,800 We featured four high-def LCD projectors in April’s “Super-size HDTV,” including the excellent $2,300 Sony VPL-HS51 and the bargain-priced $1,800 Panasonic PT-AE700U. (Going by Panasonic’s maximum recommended image size of 200 inches, that works out to a dime per square inch of picture!) Entry-level DLP-based high-def models now sell for $2,500 and up.