How to Buy a Rear-Projection TV

The oldest alternative imaging device in RPTVs is the liquid-crystal display, or LCD. Several manufacturers now use small LCD panels and high-intensity lamps to produce lightweight, high-performance rear-projection TVs. Even a 61-inch set will be less than   20 inches deep and weigh less than 100 pounds. And LCD sets can go on a shelf; floor stands are optional. Screens range from   37 inches to   61 inches diagonal, and prices range from about $1000 to $2400.

LCDs are not susceptible to burn-in and do not gradually lose brightness over time as CRTs do. On the other hand, they have a harder time producing deep blacks and gradations of dark gray, which can make LCD sets look a little washed out compared with CRTs. Manufacturers have worked hard to mitigate this weakness, however, and the best LCD projectors tend not to be as obviously challenged in this respect as they once were. All LCD rear-projection TVs are wide-screen displays, usually with a resolution of either 1280 by 720 (720p) or 1920 by 1080 (1080p).

Check the Latest Prices for Rear-Projection LCD Televisions

Liquid crystal on silicon, or LCoS (also known as D-ILA, for direct-drive image light amplifier, or SXRD, for silicon x-tal reflective display), is a liquid-crystal display technology. But unlike conventional transmissive LCD panels, LCoS chips use a reflective silicon substrate, so that light bounces off them rather than passing through. Like DLP and LCD, LCoS allows production of shallow, lightweight, high-performance displays. A big appeal of this technology has always been the tight pixel packing it allows, which helps keep the picture smooth on very big screens. Screens range from 50 inches to 70 inches diagonal; prices range from about $2300 to $6000.

The strengths of current LCoS sets are similar to those of DLP models, though the best models may provide even better blacks and dark grays. In addition, all current implementations are three-chip designs (one for each primary color), which eliminates the possibility of the "rainbow" effect that some people observe with conventional DLP models. All current LCoS sets have 1920 by 1080 (1080p) resolution and are built for table or stand mounting.

Check the Latest Prices for LCoS Televisions

To learn about other big-screen TV options, check out "How to Buy a Flat-Screen TV." And for more information on home theaters, read "How to Buy a Home Theater System."

The Specs Explained

Gone are the days when you figured out how big a screen you wanted, looked at some sets, and bought the one with the best picture that fit your budget. An options explosion has littered the shopping landscape with numbers, features, and terminology that even experts sometimes have trouble tracking. So we've tried to boil it down to the basics that can actually do you some good. (In audio and video, never forget that just because something has a number to describe it doesn't mean it really matters!)

We've divided the specs into three categories: important, somewhat important, and minor.

The aspect ratio describes the relationship of screen width to screen height. Conventional sets have a 4:3 aspect ratio, whereas wide-screen models are 16:9. Wide screen is the future. HDTV is a wide-screen format, for one thing. For another, DVDs usually look better on wide-screen displays because nearly every movie made in the last 50 years was filmed in an aspect ratio of either 1.85:1 (very close to 16:9, which is 1.78:1) or 2.35:1 (even wider than 16:9).

For CRT displays, resolution typically is specified according to standard broadcast TV formats, such as 480i, 720p, 1080i, and so forth. The 720p and 1080i formats are high definition. Non-CRT displays, such as LCDs and DLPs, are fixed-pixel arrays, which means they have rows and columns of individual picture elements that turn on and off to produce the necessary patterns of light. Resolution is usually specified as the number of pixel columns by the number of pixel rows--640 by 480, for example, or 1280 by 720.